National Primary Drinking Water Regulations: Revisions to the Total Coliform Rule

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 141 and 142

[EPA-HQ-OW-2008-0878; FRL-9684-8]

RIN 2040-AD94

National Primary Drinking Water Regulations: Revisions to the Total Coliform Rule

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Final rule.

SUMMARY:

The Environmental Protection Agency (EPA or the Agency) is finalizing revisions to the 1989 Total Coliform Rule (TCR). The Revised Total Coliform Rule (RTCR) offers a meaningful opportunity for greater public health protection beyond the 1989 TCR. Under the RTCR there is no longer a monthly maximum contaminant level (MCL) violation for multiple total coliform detections. Instead, the revisions require systems that have an indication of coliform contamination in the distribution system to assess the problem and take corrective action that may reduce cases of illnesses and deaths due to potential fecal contamination and waterborne pathogen exposure. This final rule also updates provisions in other rules that reference analytical methods and other requirements in the 1989 TCR (e.g., Public Notification and Ground Water Rules). These revisions are in accordance with the 1996 Safe Drinking Water Act (SDWA) Amendments, which require EPA to review and revise, as appropriate, each national primary drinking water regulation no less often than every six years. These revisions also conform with the SDWA provision that requires any revision to “maintain, or provide for greater, protection of the health of persons.” As with the 1989 TCR, the RTCR applies to all public water systems.

DATES:

This final rule is effective on April 15, 2013. For judicial purposes, this final rule is promulgated as of February 13, 2013. The compliance date for the rule requirements is April 1, 2016. The incorporation by reference of certain publications listed in the rule is approved by the Director of the Federal Register (FR) as of April 15, 2013.

ADDRESSES:

EPA has established a docket for this action under Docket ID No. EPA-HQ-OW-2008-0878. All documents in the docket are listed on the

http://www.regulations.gov

Web site. Although listed in the index, some information is not publicly available, e.g., Confidential Business Information or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet and will be publicly available only in hard copy form. Publicly available docket materials are available either electronically through

http://www.regulations.gov

or in hard copy at the Water Docket, EPA/DC, EPA West, Room 3334, 1301 Constitution Ave. NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Water Docket is (202) 566-2426.

FOR FURTHER INFORMATION CONTACT:

Sean Conley, Standards and Risk Management Division, Office of Ground Water and Drinking Water (MC-4607M), Environmental Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460; telephone number: (202) 564-1781; email address:

conley.sean@epa.gov.

For general information, contact the Safe Drinking Water Hotline, telephone number: (800) 426-4791. The Safe Drinking Water Hotline is open Monday through Friday, excluding legal holidays, from 10 a.m. to 4 p.m. Eastern time.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Regulated Categories and Entities

Entities potentially regulated by the RTCR are all public water systems (PWSs). Regulated categories and entities include the following:

Category

Examples of regulated entities

Industry

Privately-owned community water systems (CWSs), transient non-community water systems (TNCWSs), and non-transient non-community water systems (NTNCWSs).

Federal, State, Tribal, and local governments

Publicly-owned CWSs, TNCWSs, and NTNCWSs.

This table is not intended to be exhaustive, but rather provides a guide for readers regarding entities regulated by this action. This table lists the types of entities that EPA is now aware could potentially be regulated by this action. Other types of entities not listed in the table could also be regulated. To determine whether your facility is regulated by this action, you should carefully examine the definition of “public water system” in § 141.2 and the section entitled “Coverage” in § 141.3 in title 40 of the Code of Federal Regulations (CFR), and the applicability criteria in § 141.851(b) of this rule. If you have questions regarding the applicability of this action to a particular entity, consult the person listed in the preceding

FOR FURTHER INFORMATION CONTACT

section.

B. Copies of This Document and Other Related Information

This document is available for download at [INSERT WEBSITE ADDRESS]. For other related information, see preceding discussion on docket. EPA also prepared a

Response to Comments Document

that addresses the comments received during the comment period (to access this document, search for Docket ID No. EPA-HQ-OW-2008-0878 in

www.regulations.gov

).

C. Executive Summary

EPA is finalizing the Revised Total Coliform Rule (RTCR). The RTCR maintains the purpose of the 1989 Total Coliform Rule (TCR) to protect public health by ensuring the integrity of the drinking water distribution system and monitoring for the presence of microbial contamination. EPA anticipates greater public health protection under the RTCR, as it requires public water systems (PWSs) that are vulnerable to microbial contamination to identify and fix problems, and it establishes criteria for systems to qualify for and stay on reduced monitoring, thereby providing incentives for improved water system operation.

The RTCR, as with the 1989 TCR, is the only microbial drinking water regulation that applies to all PWSs. Systems are required to meet a legal limit (i.e., maximum contaminant level (MCL)) for

E. coli,

as demonstrated by required monitoring. The RTCR specifies the frequency and timing of the microbial testing by water systems based on population served, system type, and source water type. The rule also requires public notification when

there is a potential health threat as indicated by monitoring results, and when the system fails to identify and fix problems as required.

The entities potentially affected by the RTCR are PWSs that are classified as community water systems (CWSs) (e.g., systems that provide water to year-round residents in places like homes or apartment buildings) or non-community water systems (NCWSs) (e.g., systems that provide water to people in locations such as schools, office buildings, restaurants, etc.); State primacy agencies; and local and tribal governments. The RTCR applies to approximately 155,000 PWSs that serve approximately 310 million (M) individuals.

The RTCR establishes a health goal (maximum contaminant level goal, or MCLG) and an MCL for

E. coli,

a more specific indicator of fecal contamination and potential harmful pathogens than total coliforms. EPA replaces the MCLG and MCL for total coliforms with a treatment technique for coliforms that requires assessment and corrective action. Many of the organisms detected by total coliform methods are not of fecal origin and do not have any direct public health implication.

Under the treatment technique for coliforms, total coliforms serve as an indicator of a potential pathway of contamination into the distribution system. A PWS that exceeds a specified frequency of total coliform occurrence must conduct an assessment to determine if any sanitary defects exist (a sanitary defect is defined by the RTCR as a “defect that could provide a pathway of entry for microbial contamination into the distribution system or that is indicative of a failure or imminent failure of a barrier that is already in place”); if any are found, the system must correct them. In addition, under the treatment technique requirements, a PWS that incurs an

E. coli

MCL violation must conduct an assessment and correct any sanitary defects found.

The RTCR links monitoring frequency to compliance monitoring results and system performance. It provides criteria that well-operated small systems must meet to qualify for and stay on reduced monitoring. It requires increased monitoring for high-risk small systems with unacceptable compliance history. It also requires some new monitoring requirements for seasonal systems (such as state and national parks).

The RTCR eliminates public notification requirements based only on the presence of total coliforms. Total coliforms in the distribution system may indicate a potential pathway for contamination but by themselves do not indicate a health threat. Instead, the RTCR requires public notification when an

E. coli

MCL violation occurs, indicating a potential health threat, or when a PWS fails to conduct the required assessment and corrective action.

EPA believes that the provisions of the RTCR will improve public health protection by requiring assessment and corrective action and providing incentives for improved operation. The estimated net incremental cost of the RTCR is $14 million annually at either a three or seven percent discount rate. This represents total increased costs relative to 1989 TCR provisions. PWSs are estimated to incur approximately 97 percent of the rule's net annualized present value costs at the three percent discount rate. States and other primacy agencies incur the remaining costs.

Abbreviations Used in This Document

AGI—Acute Gastrointestinal Illness

AIDS—Acquired Immune Deficiency Syndrome

AIP—Agreement in Principle

AWWA—American Water Works Association

ATP—Alternate Test Procedure

BAT—Best Available Technology

C—Celsius

CCR—Consumer Confidence Report

CDC—Centers for Disease Control and Prevention

CFR—

Code of Federal Regulations

COI—Cost of Illness

CWS—Community Water System

DBP—Disinfection Byproduct

DWC—Drinking Water Committee

EA—Economic Analysis

EC-MUG—EC Medium with MUG

EPA—United States Environmental Protection Agency

ERS—Economic Research Service

ETV—Environmental Technology Verification

FR—

Federal Register

GWR—Ground Water Rule

GWUDI—Ground Water Under the Direct Influence of Surface Water

HRRCA—Health Risk Reduction and Cost Analysis

HUS—Hemolytic Uremic Syndrome

ICR—Information Collection Request

IESWTR—Interim Enhanced Surface Water Treatment Rule

M—Million

MCL—Maximum Contaminant Level

MCLG—Maximum Contaminant Level Goal

mg/L—Milligrams per Liter

ml—Milliliters

MRDL—Maximum Residual Disinfectant Level

MUG—4-methylumbelliferyl-Beta-D-glucuronide

NCWS—Non-community Water System

NDWAC—National Drinking Water Advisory Council

NPDWR—National Primary Drinking Water Regulation

NTNCWS—Non-Transient Non-Community Water System

NTU—Nephelometric Turbidity Unit

OMB—Office of Management and Budget

O&M—Operation and Maintenance

PN—Public Notification

PWS—Public Water System

RFA—Regulatory Flexibility Act

RTCR—Revised Total Coliform Rule

SAB—Science Advisory Board

SBA—Small Business Administration

SDWA—Safe Drinking Water Act

SDWIS—Safe Drinking Water Information System

SDWIS/FED—Safe Drinking Water Information System Federal Version

SOP—Standard Operating Procedure

Stage 1 DBPR—Stage 1 Disinfectants and Disinfection Byproducts Rule

Stage 2 DBPR—Stage 2 Disinfectants and Disinfection Byproducts Rule

SWTR—Surface Water Treatment Rule

TCR—Total Coliform Rule

TCRDSAC—Total Coliform Rule/Distribution System Advisory Committee

TMF—Technical, Managerial, and Financial

TNCWS—Transient Non-Community Water System

TWG—Technical Work Group

T&C—Technology and Cost

US—United States

UV—Ultraviolet

Table of Contents

I. General Information

A. Regulated Categories and Entities

B. Copies of This Document and Other Related Information

C. Executive Summary

II. Background

A. Statutory Authority

B. Purpose of the Rule

C. Rule Development

1. Total Coliform Rule Distribution System Advisory Committee (TCRDSAC)

2. Stakeholder Involvement

D. Public Health Concerns Addressed by the Revised Total Coliform Rule

1. Public Health Concerns, Fecal Contamination, and Waterborne Pathogens

2. Indicators

3. Occurrence of Fecal Contamination and Waterborne Pathogens

III. Requirements of the Revised Total Coliform Rule

A. RTCR Definitions

1. Assessment

2. Clean Compliance History

3. Sanitary Defect

4. Seasonal Systems

B. Rule Construct: MCLG and MCL for

E. coli

and Coliform Treatment Technique

1. MCLG and MCL

2. Coliform Treatment Technique

C. Monitoring

1. Requirements

2. Key Issues Raised

D. Repeat samples

1. Requirements

2. Key Issues Raised

E. Coliform Treatment Technique

1. Coliform Treatment Technique Triggers

2. Assessment

3. Corrective Action

F. Violations

1. Requirements

2. Key Issues Raised

G. Providing Notification and Information to the Public

1. Requirements

2. Key Issues Raised

H. Reporting and Recordkeeping

1. Requirements

2. Key Issues Raised

I. Analytical Methods

1. AIP-Related Method Issues

2. Other Method Issues

J. Systems Under EPA Direct Implementation

K. Compliance Date

IV. Other Elements of the Revised Total Coliform Rule

A. Best Available Technology

1. Requirements

2. Key Issues Raised

B. Variances and Exemptions

1. Requirements

2. Key Issues Raised

C. Revisions to Other NPDWRs as a Result of the RTCR

D. Storage Facility Inspection

V. State Implementation

A. Primacy

1. Requirements

2. Key Issues Raised

B. State Recordkeeping and Reporting and SDWIS

1. Recordkeeping

2. Reporting

3. SDWIS

4. Key Issues Raised

VI. Economic Analysis (Health Risk Reduction and Cost Analysis)

A. Regulatory Options Considered

B. Major Sources of Data and Information Used in Supporting Analyses

1. Safe Drinking Water Information System Federal version data

2. Six-Year Review 2 data

3. Other information sources

C. Occurrence and Predictive Modeling

1. Model Used for PWSs Serving ≤ 4,100 People

2. Model Used for PWSs Serving > 4,100 People

D. Baseline Profiles

E. Anticipated Benefits of the RTCR

1. Relative Risk Analysis

2. Changes in Violation Rates and Corrective Actions

3. Nonquantifiable Benefits

F. Anticipated Costs of the RTCR

1. Total Annualized Present Value Costs

2. PWS Costs

3. State Costs

4. Nonquantifiable Costs

G. Potential Impact of the RTCR on Households

H. Incremental Costs and Benefits

I. Benefits From Simultaneous Reduction of Co-occurring Contaminants

J. Change in Risk From Other Contaminants

K. Effects of Fecal Contamination and/or Waterborne Pathogens on the General Population and Sensitive Subpopulations

1. Risk to Children, Pregnant Women, and the Elderly

2. Risk to Immunocompromised Persons

L. Uncertainties in the Benefit and Cost Estimates for the RTCR

1. Inputs and Their Uncertainties

2. Sensitivity Analysis

M. Benefit Cost Determination for the RTCR

N. Comments Received in Response to EPA's Requests for Comment

1. SAB's Concerns

2. Costs of Major Distribution System Appurtenances

3. Annual Monitoring and Annual Site Visits

4. Effectiveness of Assessments

O. Other Comments Received by EPA

1. Quantifying Health Benefits

2. Return to Reduced Monitoring

3. Shift of State Resources

4. State burden

VII. Statutory and Executive Order Review

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: Improving Regulation and Regulatory Review

B. Paperwork Reduction Act

C. Regulatory Flexibility Act (RFA)

D. Unfunded Mandates Reform Act (UMRA)

E. Executive Order 13132: Federalism

F. Executive Order 13175: Consultation and Coordination With Indian Tribal Governments

G. Executive Order 13045: Protection of Children From Environmental Health Risks and Safety Risks

H. Executive Order 13211: Actions That Significantly Affect Energy Supply, Distribution, or Use

I. National Technology Transfer and Advancement Act

J. Executive Order 12898: Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations

K. Consultations With the Science Advisory Board, National Drinking Water Advisory Council, and the Secretary of Health and Human Services

L. Considerations of Impacts on Sensitive Subpopulations as Required by Section 1412(b)(3)(C)(i)(V) of the 1996 Amendments of the Safe Drinking Water Act (SDWA)

M. Effect of Compliance with the RTCR on the Technical, Financial, and Managerial Capacity of Public Water Systems

N. Congressional Review Act

VIII. References

II. Background

A. Statutory Authority

The Safe Drinking Water Act (SDWA) requires the EPA to review and revise, as appropriate, each existing national primary drinking water regulation (NPDWR) no less often than every six years (SDWA section 1412(b)(9), 42 U.S.C. 300g-1(b)(9)). In 2003, EPA completed its review of the 1989 TCR (USEPA 1989a, 54 FR 27544, June 29, 1989) and 68 NPDWRs for chemicals that were promulgated prior to 1997 (USEPA 2003, 68 FR 42908, July 18, 2003). The purpose of the review was to identify new health risk assessments, changes in technology, and other factors that would provide a health-related or technological basis to support a regulatory revision that would maintain or improve public health protection. In the Six-Year Review 1 determination published in July 2003 (USEPA 2003, 68 FR 42908, July 18, 2003), EPA stated its intent to revise the 1989 TCR.

B. Purpose of the Rule

EPA promulgated the 1989 TCR to decrease the risk of waterborne illness. Among all SDWA rules promulgated for preventing waterborne illness, only the TCR applies to all PWSs, making the rule an essential component of the multi-barrier approach in public health protection against endemic and epidemic disease. In combination with the other SDWA rules (e.g., the Ground Water Rule (GWR) (USEPA 2006c, 71 FR 65574, November 8, 2006) and the suite of surface water treatment rules (USEPA 1989b; USEPA 1998b; USEPA 2002; USEPA 2006d)), the RTCR will better address the 1989 TCR objectives and enhance the multi-barrier approach to protecting public health, especially with respect to small ground water PWSs.

In recent years, the number of violations under the 1989 TCR have remained relatively steady, as shown and discussed in Exhibit 4.11 and Appendix G of the

Economic Analysis for the Final Revised Total Coliform Rule

(RTCR EA) (USEPA 2012a). EPA believes that this is reflective of a steady state among PWSs complying with the 1989 TCR and any improvements likely to occur under that rule have largely been achieved. In outlining recommendations for further reductions in occurrence, EPA and the Total Coliform Rule Distribution System Advisory Committee (TCRDSAC) developed an Agreement in Principle (AIP) (USEPA 2008c), which became the basis of the proposed and final RTCR. See section II.C.1 of this preamble,

Total Coliform Distribution System Advisory Committee (TCRDSAC),

for more information about the TCRDSAC and the AIP.

The RTCR aims for greater public health protection than the 1989 TCR in a cost-effective manner by: (1) Maintaining the objectives of the 1989 TCR (i.e., to evaluate the effectiveness of treatment, to determine the integrity of the distribution system, and to signal the possible presence of fecal contamination); (2) reducing the potential pathways of contamination into the distribution system (see section II.D of this preamble,

Public Health Concerns Addressed by the Revised Total Coliform Rule

); (3) using the optimal indicator for the intended objectives (i.e., using total coliforms as an indicator of system operation and

condition rather than an immediate public health concern and using

E. coli

as a fecal indicator (see sections II.D,

Public Health Concerns Addressed by the Revised Total Coliform Rule,

and III.B,

Rule Construct: MCLG and MCL for E. coli and Coliform Treatment Technique,

of this preamble)); (4) requiring more stringent standards than those of the 1989 TCR for systems to qualify for reduced monitoring (see sections III.C.1.b.iii,

Reduced monitoring,

and III.C.1.c.iii,

Reduced monitoring,

of this preamble); and (5) requiring systems that may be vulnerable to contamination, as indicated by their monitoring results and by the nature of their operation (e.g., seasonal systems), to monitor more frequently and have in place procedures that will minimize the incidence of contamination (e.g., requiring start-up procedures for seasonal systems) (see sections III.C.1.b.iv,

Increased monitoring,

III.C.1.c.iv,

Requirements for returning to monthly monitoring,

and III.C.1.f,

Seasonal systems,

of this preamble). EPA, therefore, anticipates greater public health protection under the RTCR compared to the 1989 TCR because of the RTCR's more preventive approach to identifying and fixing problems that affect or may affect public health.

C. Rule Development

1. Total Coliform Rule Distribution System Advisory Committee (TCRDSAC)

The revisions to the 1989 TCR are primarily based on the recommendations of the Total Coliform Rule Distribution System Advisory Committee (“TCRDSAC” or the “advisory committee”). EPA established the TCRDSAC in June 2007 in accordance with the provisions of the Federal Advisory Committee Act, 5 U.S.C. App.2, 9(c), to provide recommendations to EPA on revisions to the 1989 TCR and on what information about distribution system issues is needed to better understand and address possible public health impacts from potential degradation of drinking water quality in distribution systems (USEPA 2007a, 72 FR 35869, June 29, 2007).

All advisory committee members agreed to a set of recommendations and signed a final Agreement in Principle (AIP) in September 2008. Pursuant to the AIP, EPA on July 14, 2010 proposed revisions to the 1989 TCR (USEPA 2010a, 75 FR 40926, July 14, 2010) that, to the maximum extent consistent with EPA's legal obligations, had the same substance and effect as the elements of the AIP. The AIP and details about the advisory committee can be found at EPA's Web site at

http://water.epa.gov/lawsregs/rulesregs/sdwa/tcr/regulation_revisions_tcrdsac.cfm.

2. Stakeholder Involvement

In accordance with one of the recommendations of the TCRDSAC, EPA held two annual stakeholder meetings, prior to publishing the proposed revisions, to which all advisory committee members and the public at large were invited. In April 2009 and May 2010, EPA held these stakeholder meetings to provide updates and an opportunity for stakeholders to provide feedback on the development of a proposed RTCR that had the same substance and effect as the recommendations in the AIP.

EPA proposed the RTCR on July 14, 2010 (USEPA 2010a, 75 FR 40926, July 14, 2010) and requested public comment. EPA received approximately 150 comment letters on the proposal and considered the comments in making revisions to the final RTCR. Key issues raised by the commenters are discussed in their corresponding sections of this preamble. A

Response to Comments Document

is available in the docket of the RTCR (search for Docket ID No. EPA-HQ-OW-2008-0878 in

www.regulations.gov

).

During the public comment period for the proposed RTCR, EPA also held several meetings to solicit and provide the public with information about the provisions of the proposed rule. In addition to consulting with the advisory committee and holding stakeholder meetings, EPA consulted with specific stakeholders such as the National Drinking Water Advisory Council (NDWAC), the Science Advisory Board (SAB), and Tribal representatives, among others. These consultations are discussed in section VII of this preamble,

Statutory and Executive Order Review.

D. Public Health Concerns Addressed by the Revised Total Coliform Rule

1. Public Health Concerns, Fecal Contamination, and Waterborne Pathogens

The RTCR aims to increase public health protection through the reduction of potential pathways of entry for fecal contamination into the distribution system. Since these potential pathways represent vulnerabilities in the distribution system whereby fecal contamination and/or waterborne pathogens, including bacteria, viruses and parasitic protozoa could possibly enter the system, the reduction of these pathways in general should lead to reduced exposure and associated risk from these contaminants. Fecal contamination and waterborne pathogens can cause a variety of illnesses, including acute gastrointestinal illness (AGI) with diarrhea, abdominal discomfort, nausea, vomiting, and other symptoms. Most AGI cases are of short duration and result in mild illness. Other more severe illnesses caused by waterborne pathogens include hemolytic uremic syndrome (HUS) (kidney failure), hepatitis, and bloody diarrhea (WHO 2004). Chronic disease such as irritable bowel syndrome, renal impairment, hypertension, cardiovascular disease and reactive arthritis can result from infection by a waterborne agent (Clark

et al.

2008; Clark

et al.

2010; Moorin

et al.

2010).

When humans are exposed to and infected by waterborne enteric pathogens, the pathogens become capable of reproducing in the gastrointestinal tract. As a result, healthy humans shed pathogens in their feces for a period ranging from days to weeks. This shedding of pathogens often occurs in the absence of any signs of clinical illness. Regardless of whether a pathogen causes clinical illness in the person who sheds it in his or her feces, the pathogen being shed may infect other people directly by person-to-person spread, contact with contaminated surfaces, and other means referred to as secondary spread. As a result, waterborne pathogens that are initially waterborne may subsequently infect other people through a variety of routes (WHO 2004). Sensitive subpopulations are at greater risk from waterborne disease than the general population (Gerba

et al.

1996). For a discussion of sensitive subpopulations, see section VII.L of this preamble,

Impacts on Sensitive Subpopulations as Required by Section 1412(b)(3)(c)(i)(V) of the 1996 Amendments of the Safe Drinking Water Act (SDWA).

2. Indicators

Total coliforms are a group of closely related bacteria that, with a few exceptions, are not harmful to humans. Coliforms are abundant in the feces of warm-blooded animals, but can also be found in aquatic environments, in soil, and on vegetation. Coliform bacteria may be transported to surface water by run-off or to ground water by infiltration. Total coliforms are common in ambient water and may be injured by environmental stresses such as lack of nutrients, and water treatments such as chlorine disinfection, in a manner similar to most bacterial pathogens and

many viral enteric pathogens (including fecal pathogens). EPA considers total coliforms to be a useful indicator that a potential pathway exists through which fecal contamination can enter the distribution system. This is because the absence (versus the presence) of total coliforms in the distribution system indicates a reduced likelihood that fecal contamination and/or waterborne pathogens are occurring in the distribution system.

Under the 1989 TCR, each total coliform-positive sample is assayed for either fecal coliforms or

E. coli.

Fecal coliform bacteria are a subgroup of total coliforms that traditionally have been associated with fecal contamination. Since the promulgation of the 1989 TCR, more information and understanding of the suitability of fecal coliform and

E. coli

as indicators have become available. Study has shown that the fecal coliform assay is imprecise and too often captures bacteria that do not originate in the human or mammal gut (Edberg

et al.

2000). On the other hand,

E. coli

is a more restricted group of coliform bacteria that almost always originate in the human or animal gut (Edberg

et al.

2000). Thus,

E. coli

is a better indicator of fecal contamination than fecal coliforms. The provisions of the RTCR reflect the improved understanding of the value of total coliforms and

E. coli

as indicators.

3. Occurrence of Fecal Contamination and Waterborne Pathogens

a. Presence of fecal contamination.

Fecal contamination is a very general term that includes all of the organisms found in feces, both pathogenic and nonpathogenic. Fecal contamination can occur in drinking water both through use and inadequate treatment of contaminated source water as well as direct intrusion of fecal contamination into the drinking water distribution system. Lieberman

et al.

(1994) discuss the general association between fecal contamination and waterborne pathogens. Biofilms in distribution systems may harbor waterborne bacterial pathogens and accumulate enteric viruses and parasitic protozoa (Skraber

et al.

2005; Helmi

et al.

2008). Waterborne pathogens in biofilms may have entered the distribution system as fecal contamination from humans or animals.

Co-occurrence of indicators and waterborne pathogens is difficult to measure. While the analytical methods approved by EPA to assay for

E. coli

are able to detect indicators of fecal contamination, they do not specifically identify most of the pathogenic

E. coli

strains. There are at least 700 recognized

E. coli

strains (Kaper

et al.

2004) and about 10 percent of recognized

E. coli

strains are pathogenic to humans (Feng 1995; Hussein 2007; Kaper

et al.

2004). Pathogenic

E. coli

include

E. coli

O157:H7, which is the primary cause of HUS in the United States (Rangel

et al.

2005). The US Centers for Disease Control and Prevention (CDC) estimates that there are 73,000 cases of illness each year in the US due to

E. coli

O157:H7 (Mead

et al.

1999). The CDC estimates that about 15 percent of all reported

E. coli

O157:H7 cases are due to water contamination (Rangel

et al.

2005). Active surveillance by CDC shows that 6.3 percent of

E. coli

O157:H7 cases progress to HUS (Griffin and Tauxe 1991; Gould

et al.

2009) and about 12 percent of HUS cases result in death within four years (Garg

et al.

2003). About 4 to 15 percent of cases are transmitted within households by secondary transmission (Parry and Salmon 1998).

Because EPA-approved standard methods for

E. coli

do not typically identify the presence of the pathogenic

E. coli

strains, an

E. coli

-positive monitoring result is an indicator of fecal contamination but is not necessarily a measure of waterborne pathogen occurrence. Specialized assays and methods are used to identify waterborne pathogens, including pathogenic

E. coli.

One notable exception is the data reported by Cooley

et al.

(2007), which showed high concentrations of pathogenic

E. coli

strains in samples containing high concentrations of fecal indicator

E. coli.

These data are from streams and other poor quality surface waters surrounding California spinach fields associated with the 2006

E. coli

O157:H7 foodborne outbreak. Data equivalent to these samples are not available from drinking water samples collected under the 1989 TCR.

Because

E. coli

is an indicator of fecal contamination (Edberg

et al.

2000), and because of the general association between fecal contamination and waterborne pathogens (Lieberman

et al.

1994; Lieberman

et al.

2002),

E. coli

is a meaningful indicator for fecal contamination and the potential presence of associated pathogen occurrence.

b. Waterborne disease outbreaks.

The CDC defines a waterborne disease outbreak as occurring when at least two persons experience a similar illness after ingesting a specific drinking water (or after exposure to recreational water) contaminated with pathogens (or chemicals) (Kramer

et al.

1996), or when one person experiences amoebic meningoencephalitis after similar waterborne exposure. The CDC maintains a database on waterborne disease outbreaks in the United States. The database is based upon responses to a voluntary and confidential survey form that is completed by State and local public health officials.

The National Research Council strongly suggests that the number of identified and reported outbreaks in the CDC database for surface and ground waters represents only a small percentage of the actual number of waterborne disease outbreaks (NRC 1997; Bennett

et al.

1987; Hopkins

et al.

1985 for Colorado data). Under-reporting occurs because most waterborne outbreaks in community water systems are not recognized until a sizable proportion of the population is ill (Perz

et al.

1998; Craun 1996), perhaps 1 percent to 2 percent of the population (Craun 1996). EPA drinking water regulations are designed to protect against endemic waterborne disease and to minimize waterborne outbreaks. In contrast to outbreaks, endemic disease refers to the persistent low to moderate level or the usual ongoing occurrence of illness in a given population or geographic area (Craun

et al.

2006).

III. Requirements of the Revised Total Coliform Rule

The RTCR maintains and strengthens the objectives of the 1989 TCR and is consistent with the recommendations in the AIP. The objectives are: (1) To evaluate the effectiveness of treatment, (2) to determine the integrity of the distribution system, and (3) to signal the possible presence of fecal contamination. The RTCR better addresses these objectives by requiring systems that may be vulnerable to fecal contamination (as indicated by their monitoring results) to do an assessment, to identify whether any sanitary defect(s) is (are) present, and to correct the defects. Therefore, the Agency anticipates greater public health protection under the RTCR compared to the 1989 TCR because of its more preventive approach to identifying and fixing problems that affect or may affect public health. The following is an overview of the key provisions of the RTCR:

•

MCLG and MCL for E. coli and coliform treatment technique for protection against potential fecal contamination.

The RTCR establishes a maximum contaminant level goal (MCLG) and maximum contaminant level (MCL) for

E. coli.

Under the RTCR there is no longer a monthly maximum contaminant level (MCL) violation for multiple total coliform detections. The RTCR takes a preventive approach to protecting public health by establishing

a coliform treatment technique for protection against potential fecal contamination. The treatment technique uses both total coliforms and

E. coli

monitoring results to start an evaluation process that, where necessary, requires the PWS to conduct follow-up corrective action that could prevent future incidences of contamination and exposure to fecal contamination and/or waterborne pathogens. See section III.B of this preamble,

Rule Construct: MCLG and MCL for E. coli and Coliform Treatment Technique,

for further discussion on the MCLG, MCL, and treatment technique requirements.

•

Monitoring.

As with the 1989 TCR, PWSs will continue to monitor for total coliforms and

E. coli

according to a sample siting plan and schedule specific to the system.

Sample siting plans under the RTCR must continue to be representative of the water throughout the distribution system. Under the RTCR, systems have the flexibility to propose repeat sample locations that best verify and determine the extent of potential contamination of the distribution system rather than having to sample within five connections upstream and downstream of the total coliform-positive sample location. In lieu of proposing new repeat sample locations, the systems may stay with the default used under the 1989 TCR of within-five-connections-upstream-and-downstream of the total coliform-positive sample location.

As with the 1989 TCR, the RTCR allows reduced monitoring for some small ground water systems. The RTCR is expected to improve public health protection compared to the 1989 TCR by requiring small ground water systems that are on or wish to conduct reduced monitoring to meet certain eligibility criteria. Examples of the criteria include a sanitary survey showing that the system is free of sanitary defects, a clean compliance history for 12 months, and a recurring annual site visit by the State and/or a voluntary Level 2 assessment for systems on annual monitoring.

For small ground water systems, the RTCR requires increased monitoring for high-risk systems such as those that do not have a clean compliance history under the RTCR. The RTCR specifies conditions under which systems will no longer be eligible for reduced monitoring and be required to return to routine monitoring or to monitor at an increased frequency.

The RTCR requires systems on a quarterly or annual monitoring frequency (applicable only to ground water systems serving 1,000 or fewer people) to collect at least three additional routine monitoring samples the month following one or more total coliform-positive samples, unless the State waives the additional routine monitoring. This is a reduction in the required number of additional routine samples from the 1989 TCR, which requires at least five routine samples in the month following a total coliform-positive sample for all systems serving 4,100 or fewer people.

The 1989 TCR requires all systems serving 1,000 or fewer people to collect at least four repeat samples while requiring PWSs serving 1,000 people or greater to collect three repeat samples. The RTCR requires three repeat samples after a routine total coliform-positive sample, regardless of the system type and size.

See sections III.C,

Monitoring,

and III.D,

Repeat Samples,

of this preamble for detailed discussions of the routine monitoring and repeat sampling requirements of the RTCR.

•

Seasonal systems.

For the first time, the RTCR establishes monitoring requirements specific to seasonal systems. Seasonal systems represent a special case in that the shutdown and start-up of these water systems present additional opportunities for contamination to enter or spread through the distribution system. Under the RTCR, seasonal systems must demonstrate completion of a State-approved start-up procedure. See sections III.A.4,

Seasonal systems,

and III.C.1.f,

Seasonal systems,

of this preamble for further discussion of requirements for seasonal systems.

•

Assessment and corrective action.

As part of a treatment technique, all PWSs are required to assess their systems when monitoring results show that the system may be vulnerable to contamination. Systems must conduct either a Level 1 assessment or a more detailed Level 2 assessment depending on the level of concern raised by the results of indicator sampling. The system is responsible for correcting any sanitary defect(s) found through either a Level 1 or Level 2 assessment. See section III.E of this preamble,

Coliform Treatment Technique,

for more discussion of the treatment technique requirement of the RTCR.

•

Violations and public notification.

The RTCR establishes an

E. coli

MCL violation, a treatment technique violation, a monitoring violation, and a reporting violation. Public notification is required for each type of violation, with the type of notification dependent on the degree of potential public health concern. This is consistent with EPA's current public notification requirements under 40 CFR part 141 subpart Q. The RTCR also modifies the public notification and Consumer Confidence Report language to reflect the construct of the rule. See sections III.F,

Violations,

and III.G,

Providing Notification and Information to the Public,

of this preamble for further discussions of violations and public notification under the RTCR.

•

Transition to the RTCR.

The RTCR allows all systems to transition to the new rule at their 1989 TCR monitoring frequency, including systems on reduced monitoring under the 1989 TCR. For ground water systems serving 1,000 or fewer people, States must conduct a special monitoring evaluation during each sanitary survey after the compliance effective date of the RTCR. Initial grandfathering of monitoring frequencies reduces State burden by not requiring the State to determine appropriate monitoring frequency at the same time the State is working to adopt primacy, develop policies, and train their own staff and the PWSs in the State.

The provisions of the RTCR are contained in the new 40 CFR part 141 subpart Y, superseding 40 CFR 141.21 beginning April 1, 2016.

A. RTCR Definitions

1. Assessment

a. Provisions.

EPA is defining a Level 1 assessment and a Level 2 assessment to help in the implementation of the RTCR and to better differentiate between the two levels of assessments.

A Level 1 assessment is an evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices, and (when possible) the likely reason that the system triggered the assessment. It is conducted by the system operator or owner (or his designated representative). Minimum elements include review and identification of atypical events that could affect distributed water quality or indicate that distributed water quality was impaired; changes in distribution system maintenance and operation that could affect distributed water quality (including water storage); source and treatment considerations that bear on distributed water quality, where appropriate (e.g., whether a ground water system is disinfected); existing water quality monitoring data; and inadequacies in sample sites, sampling protocol, and sample processing. The system must conduct the assessment consistent with any State directives that tailor specific assessment elements with respect to the size and type of the system and the size, type, and

characteristics of the distribution system.

A Level 2 assessment is an evaluation to identify the possible presence of sanitary defects, defects in distribution system coliform monitoring practices, and (when possible) the likely reason that the system triggered the assessment. A Level 2 assessment provides a more detailed examination of the system (including the system's monitoring and operational practices) than does a Level 1 assessment through the use of more comprehensive investigation and review of available information, additional internal and external resources, and other relevant practices. It is conducted by an individual approved by the State, which may include the system operator. Minimum elements include review and identification of atypical events that could affect distributed water quality or indicate that distributed water quality was impaired; changes in distribution system maintenance and operation that could affect distributed water quality (including water storage); source and treatment considerations that bear on distributed water quality, where appropriate (e.g., whether a ground water system is disinfected); existing water quality monitoring data; and inadequacies in sample sites, sampling protocol, and sample processing. The system must conduct the assessment consistent with any State directives that tailor specific assessment elements with respect to the size and type of the system and the size, type, and characteristics of the distribution system. The system must comply with any expedited actions or additional actions required by the State in the case of an

E. coli

MCL violation.

b. Key issues raised.

EPA did not propose definitions for Level 1 and Level 2 assessments. However, based on the comments EPA received, there was concern that the distinction between the two levels of assessment is not sufficiently laid out in the rule language. This might pose some problems in the implementation of the RTCR. In response, EPA is defining a Level 1 assessment and a Level 2 assessment. This issue and the RTCR requirements regarding assessments are discussed further in section III.E.2 of this preamble,

Assessment.

2. Clean Compliance History

a. Provisions.

In the final RTCR, EPA is defining “clean compliance history” as a record of no maximum contaminant level (MCL) violations under 40 CFR 141.63; no monitoring violations under 40 CFR 141.21 or subpart Y; and no coliform treatment technique trigger exceedances or coliform treatment technique violations under subpart Y. This is the same definition that the advisory committee recommended in the AIP and that EPA proposed in July 2010 (USEPA 2010a, 75 FR 40926, July 14, 2010). The term is specific to RTCR compliance and is used to determine eligibility of systems for reduced monitoring. It does not include violations under other existing NPDWRs. Systems must have a “clean compliance history” for a minimum of 12 months to qualify for reduced monitoring (see sections III.C.1.b.iii,

Reduced monitoring,

and III.C.1.c.iii,

Reduced monitoring,

of this preamble regarding reduced monitoring).

However, while the definition of “clean compliance history” includes only 1989 TCR/RTCR violations, the State may (and should) consider compliance history under other rules if relevant. For example, failure to take a triggered source water sample required under the GWR (USEPA 2006, 71 FR 65574, November 8, 2006) may appropriately cause the State to not allow less frequent monitoring because this could (1) lead the system to miss source water contamination and (2) indicate a system's lack of attention to regulatory requirements or proper operation.

b. Key issues raised.

EPA received comments that a record of no monitoring violations should not be included in the definition of “clean compliance history.” Commenters are concerned that small systems, which experience frequent turnover or shortage of staff, may not be able to qualify for reduced monitoring if they miss a sample or two. EPA believes that a system on a reduced monitoring frequency (i.e., less than monthly, either quarterly or annually) must be able to demonstrate that it is capable of delivering safe water and maintaining proper attention to the water system, even on an infrequent monitoring schedule, by meeting certain criteria (see sections III.C.1.b.iii,

Reduced monitoring,

and III.C.1.c.iii,

Reduced monitoring,

of this preamble for discussion about the reduced monitoring criteria). Small systems monitoring less frequently than monthly, especially those monitoring only annually, already have a lower probability of detecting a contamination event compared to systems that monitor monthly. Because of the intermittent nature of contamination and the fact that these systems are already on a significantly reduced monitoring frequency, it is very important that these systems take their samples as required. Because these systems monitor so infrequently, EPA recommends that the States use the annual site visits as an opportunity to review system operations, reinforce the importance of collecting the required samples, and to identify and require correction of any sanitary defects. The State can make sure that the system takes its required sample, and therefore avoids incurring a monitoring violation because of a missed sample (see section III.C.1.b.iii of this preamble,

Reduced monitoring,

for discussion of annual monitoring). EPA is therefore retaining the definition of “clean compliance history” as proposed because EPA believes that removing the record of no monitoring violation from the definition would be less protective of public health. However, EPA is providing flexibility to the States in considering monitoring violations in TNCWSs when determining whether the system must go on increased monthly monitoring. See sections III.C.1.b,

Ground water NCWSs serving ≤ 1,000 people,

and III.C.2.b,

Ground water NCWSs serving ≤ 1,000 people,

of this preamble for a more detailed discussion.

3. Sanitary Defect

a. Provisions.

EPA is finalizing the definition of sanitary defect as proposed in July 2010 (USEPA 2010a, 75 FR 40926, July 14, 2010). It is defined as a “defect that could provide a pathway of entry for microbial contamination into the distribution system or that is indicative of a failure or imminent failure in a barrier that is already in place.” As stated in the proposed rule, the first part of the definition focuses on the problems in the distribution system that may provide a pathway for contaminants to enter the distribution system and its implication for potential exposure to both microbial and chemical contaminants. The second part of the definition also recognizes the importance of having barriers in place to prevent the entry of microbial contaminants into the distribution system. Indications of failure or imminent failure of these barriers are defects that require corrective action.

The advisory committee deliberated on the definition of sanitary defect and suggested that the definition should be broad enough to facilitate corrective action without absolute confirmation of cause and effect, as such confirmation may be impossible or may significantly delay corrections that would address a sanitary defect that represents a potential threat to public health. Conversely, the language is not intended to suggest that corrections must be undertaken where the linkage between the defect and public health is tenuous. The advisory committee also agreed that

it is their intent that nothing in the definition of sanitary defects precludes conducting an assessment of every element on the example checklists for Level 1 and Level 2 assessments (USEPA 2008d).

b. Key issues raised.

EPA received comments regarding the relationship between sanitary defects under the RTCR and “significant deficiencies' under other regulations and the possible confusion between the two terms. One commenter said that the requirement to identify and correct sanitary defects under the RTCR is very similar to the GWR's requirement to identify and correct significant deficiencies, and that EPA should therefore consider which rule is more effective at minimizing risk of contamination.

The advisory committee specifically stated that “sanitary defects” are specific to the assessment and corrective action requirements of the RTCR and are not intended to be linked directly to “significant deficiencies” under the Interim Enhanced Surface Water Treatment Rule (IESWTR) (USEPA 1998, 63 FR 69389, December 16, 1998) and the GWR, although some problems could meet either definition. The term “significant deficiency” is tied or associated with the eight elements of a sanitary survey. There are problems that are “sanitary defects” and are also “significant deficiencies”. For instance, source water problems like those associated with the well casing may fit the definition of both a “sanitary defect” and a “significant deficiency.” Depending on when the problem was identified (i.e., during a sanitary survey or during an assessment triggered under RTCR) and on the guidelines set by the State, the system should coordinate with their State regarding how to characterize the problem and how to coordinate the corrective action requirements under the GWR and RTCR, if needed. Conversely, there are problems that are “sanitary defects” but are not “significant deficiencies” and vice versa. “Significant deficiency” can include problems other than those in the distribution system that can have an effect on the long term viability of the system in delivering safe water to its customers. “Significant deficiencies” can also exist in the areas of reporting and data verification, system management and operation, and operator compliance with State requirements, which are not considered “sanitary defects.”

Furthermore, although there might be overlap between a “sanitary defect” and “significant deficiency,” there are differences in the required timeframes for responding to them (see 40 CFR 141.403(a)(5) and 142.16(b)(1)(ii), and §§ 141.859(b)(3) and (b)(4) of the RTCR). It might therefore be more confusing to use only one term for the requirements of the GWR and RTCR, as suggested by some commenters.

In addition, the GWR only applies to ground water systems. Relying only on the corrective action provisions of the GWR (triggered by a fecal indicator-positive sample) will leave out those systems not covered by the GWR. Also, these GWR provisions are focused on the source water. Since contamination is intermittent and can be from a location other than the source water, the assessment and corrective action provisions in the RTCR will help to better address other types of defects.

As noted in the preamble to the proposed RTCR, nothing in the RTCR is intended to limit the existing authorities of States under other regulations.

4. Seasonal Systems

a. Provisions.

EPA is finalizing the definition of seasonal system as “a non-community water system that is not operated on a year-round basis and starts up and shuts down at the beginning and end of each operating season.”

The advisory committee recognized that seasonal systems have unique characteristics that make them susceptible to contamination. As their name implies, seasonal systems are not operated year-round. The depressurizing and dewatering of the water system, as often occurs with the temporary shutdown of the system, present opportunities for contamination to enter or spread through the distribution system. For example, loss of pressure after a system's shutdown can lead to intrusion of contaminants. Even a system that remains pressurized may be subject to water quality degradation due to stagnant water or loss of disinfectant residual. Microbial growth prior to start-up can result in biofilm formation, which can lead to the accumulation of contaminants. These systems are also more susceptible to contamination due to changes in the conditions of the source water (such as variable contaminant loading due to increased septic tank or septic field use), the seasonal nature of the demand, and the stress that the system experiences. As a result, the Agency is establishing a definition for seasonal systems and setting forth provisions that mitigate the risk associated with the unique characteristics of this type of system (see section III.C.1.f of this preamble,

Seasonal systems,

for requirements for seasonal systems). The advisory committee recommended that such provisions pertain to seasonal systems.

The definition of seasonal system that EPA is promulgating with this final rule is different from the definition proposed in July 2010 (USEPA 2010a, 75 FR 40926, July 14, 2010), which is “a non-community water system that is operated in three or fewer calendar quarters per calendar year.” As discussed in the preamble to the proposed rule, EPA was aware of the limitations of the proposed definition that could lead to less public health protection and less effective and more complicated implementation. EPA gave the example of a system that is operated from March to October. Such a system would operate in all four calendar quarters and therefore would not be considered a seasonal system according to the proposed definition, but would nonetheless be subject to the same possibility of distribution system contamination as a seasonal system operated from April to November (i.e., in only three calendar quarters). To address limitations such as this, EPA specifically requested comment on the proposed definition of a seasonal system. The change in the definition from the proposed rule is based on the comments received. Specific requirements (e.g., monitoring, start-up procedure, etc.) for seasonal systems that address the issues associated with such systems are discussed in section III.C.1.f,

Seasonal systems,

and III.C.2.c,

Seasonal systems,

of this preamble.

The definition does not include intermittent systems, such as those that are open year-round but are not operated continuously (e.g., a church open only on Saturdays and Sundays). It also does not include systems that operate year-round but may shut down part of their distribution system for part of the year (e.g., parts of the distribution system that serve a factory that is open only certain times of the year). Since these systems might be subject to the same type of risks as seasonal systems, States may want to consider whether to establish requirements that will mitigate the risks associated with their operation.

b. Key issues raised.

EPA received many responses regarding the definition of a seasonal system. Many commenters suggested addressing the issue of depressurization and dewatering in the definition. They suggested that the important risk factor is not the number of quarters the system is in operation but rather the closure and the depressurization and/or dewatering of the distribution system. Other commenters expressed concern about contamination associated with lack of water movement and loss of disinfectant

residual even in a pressurized system. Although the definition of seasonal systems does not directly address these issues, seasonal systems are required to perform start-up procedures (which may include disinfection, flushing, and coliform sampling) prior to serving water to the public. See section III.C.1.f of this preamble,

Seasonal systems,

for a discussion of the requirements for seasonal systems. EPA believes that it is important for a seasonal system to perform start-up procedures to mitigate the public health risks associated with stagnant water and the depressurization and/or dewatering of the distribution system. Hence, failure to perform start-up procedures will result in a treatment technique violation. See section III.F.b of this preamble,

Coliform treatment technique violation,

for additional discussion on this violation.

Since it is possible and perhaps likely that some systems may keep the distribution system pressurized while out of season, EPA has included an additional provision in the RTCR whereby a State can exempt any seasonal system from some or all of the requirements for seasonal systems if the entire distribution system remains pressurized during the entire period that the system is not operating (see §§ 141.854(i)(3), 141.856(a)(4)(ii), and 141.857(a)(4)(ii) of the RTCR). In providing such exemption, the State should conclude that public health protection is maintained. However, a seasonal system monitoring less frequently than monthly must still monitor during the vulnerable period designated by the State. See section III.C.1.f of this preamble,

Seasonal systems,

for additional discussion.

Some commenters suggested that seasonal systems be defined by the number of days, months, or quarters they are not in operation, e.g., 30, 60, or 90 consecutive days, three or more consecutive months, one full calendar quarter, etc. While such a change could address some of EPA's concerns, it does not address the potential for contamination associated with lack of operation and loss of pressure.

B. Rule Construct: MCLG and MCL for E. coli and Coliform Treatment Technique

1. MCLG and MCL

a. Requirements.

Under the final RTCR, EPA is eliminating the MCLG for total coliforms (including fecal coliforms) and the MCL for total coliforms. EPA is also establishing an MCLG of zero and an MCL for

E. coli.

The MCL for

E. coli

is based on the monitoring results for total coliforms and

E. coli.

A system is in compliance with the

E. coli

MCL unless any of the following conditions occur:

• A system has an

E. coli

-positive repeat sample following a total coliform-positive routine sample; or

• A routine sample is

E. coli

-positive and one of its associated repeat samples is total coliform-positive; or

• A system fails to test for

E. coli

when any repeat sample tests positive for total coliforms; or

• A system fails to take all required repeat samples following a routine sample that is positive for

E. coli.

Although not explicitly stated, as a logical consequence of the second condition, a system also violates the MCL when an

E. coli

-positive routine sample is followed by an

E. coli-

positive repeat sample because

E. coli

bacteria are a subset of total coliforms.

EPA is establishing an MCLG of zero for

E. coli

and removing the current MCLG of zero for total coliforms (including fecal coliforms) because

E. coli

is a more specific indicator of fecal contamination and potential harmful pathogens in drinking water than are total coliforms (including fecal coliforms). These requirements were part of the July 2010 proposed rule (USEPA 2010a, 75 FR 40926, July 14, 2010) and are unchanged in the final RTCR. See section III.A.2 of the preamble to the proposed RTCR,

MCLG and MCL for E. coli, and coliform treatment technique,

for further discussion on the MCLG, MCL, and treatment technique requirements.

b. Key issues raised.

The majority of the commenters supported EPA's proposal to remove the MCLG and MCL for total coliforms (including fecal coliforms) and to establish an MCLG and MCL for

E. coli.

However, there were some who commented that removing the MCLG and MCL for total coliforms will result in backsliding in public health protection. These commenters stated that the elimination of the non-acute MCL violation removes a strong incentive for water systems to perform proactive maintenance and operations activities to maintain distribution system water quality and avoid MCL violations and subsequent public notice to customers. EPA disagrees. EPA and the advisory committee decided that removing the MCLG and MCL for total coliforms is appropriate. SDWA section 1412(b)(3)(A)(i) directs EPA to use “the best available, peer-reviewed science and supporting studies conducted in accordance with sound and objective science practices” in conducting the risk assessment when promulgating an NPDWR. In 1989, EPA set an MCLG of zero for total coliforms. Since the promulgation of the 1989 TCR, a better understanding of the nature of total coliforms, especially fecal coliforms, has become available. Many of the organisms detected by total coliform and fecal coliform methods are not of fecal origin and do not have any direct public health implications (Edberg

et al.

2000). Total coliforms may, however, indicate the presence of a pathway by which fecal contamination can occur; thus, total coliforms are instead used as part of a treatment technique requirement, which is discussed in more detail in the next section and in section III.E of this preamble,

Coliform Treatment Technique

. Inclusion of the MCLG and MCL for total coliforms is not supported by the available science and would be contrary to SDWA section 1412(b)(3)(A)(i).

Commenters agreed with EPA's proposal to eliminate the provisions on fecal coliforms. Therefore, fecal coliforms will no longer be used in the RTCR and all analytical methods used to detect for fecal coliforms are also removed from the rule. For a discussion on analytical methods, see section III.I of this preamble,

Analytical Methods

.

2. Coliform Treatment Technique

a. Requirements.

EPA is establishing a treatment technique that will require a PWS to conduct an assessment of its system and, when necessary, perform corrective actions in response to trigger conditions that indicate a possible pathway of contamination into the system. The treatment technique requirements are the same as those in the proposed RTCR. A PWS that exceeds a specified frequency of total coliform occurrence must conduct a Level 1 or Level 2 assessment to determine if any sanitary defect exists and, if found, to correct the sanitary defect. As discussed earlier, the MCLG and MCL for total coliforms are removed. The conditions that defined a non-acute MCL violation under the 1989 TCR are now used to trigger a system to conduct an assessment of the system. A discussion of the treatment technique requirements, i.e., the triggers, the levels of assessment, the completion of the assessment form, etc., can be found in section III.E of this preamble,

Coliform Treatment Technique

.

b. Key issues raised.

The majority of the commenters supported the change from a total coliform non-acute MCL to a treatment technique requirement. However, some commenters disagreed with the change. They stated that the treatment technique construct will not work for small NCWSs since they typically do not treat their water, have

no certified operator, and have limited or no distribution system. They noted that since systems with limited or no distribution system do not have the extensive network of piping and service connections and other elements that comprise a typical distribution system, the treatment technique construct, which the commenters considered as focusing on the distribution system, will not work. These commenters suggested that for systems with limited or no distribution system, the focus should be on the source, and therefore, the requirements of the GWR should be sufficient. They suggested that the total coliform MCL should be retained for these systems because the treatment technique requirements will be too complicated for these systems to comply with, resulting in more non-compliance, more burden on the State, and likely less public health protection.

EPA disagrees that the treatment technique construct will not work for small NCWSs. The requirement to assess the system after a trigger consists of looking at all of the elements that might have affected the quality of the distributed water, including not only the distribution system but also the source and the treatment process. Although some small systems have limited or no distribution system, they can still have parts of their system (e.g., building plumbing, or buried piping at a campground) that are vulnerable to contamination, such as that introduced by a cross-connection or infiltration. In addition, relying only on the corrective action provisions of the GWR will leave out those systems not covered by the GWR, or in cases of positive results, systems where corrective action under the GWR is not immediately required by the State. For example, total coliform-positive repeat samples do not trigger any action under the GWR, even if those samples are also triggered source water samples. Also, a State may require additional source samples instead of a corrective action after the first fecal indicator positive sample (see 40 CFR 141.402(a)(3)). In addition, some small NCWSs with limited or no distribution system use surface water. Finally, the GWR provisions are focused on the source water. Since contamination is intermittent and can be from a location other than the source water, the assessment and corrective action provisions in the RTCR will help address other types of defects.

EPA understands that there will be implementation challenges during the first few years of the rule implementation, especially for small PWSs. However, as systems with limited or no distribution system are simple systems, the assessments should also be relatively simple. There is nothing in the RTCR that prohibits the States from conducting assessments that integrate the requirements of the GWR and RTCR where appropriate (see section III.E of this preamble,

Coliform Treatment Technique,

for a discussion of the coliform treatment technique). EPA encourages States to make any necessary modifications to their regulations to make the most efficient use of limited State resources and to better integrate these rules for systems with little-to-no distribution system, provided that the revisions satisfy the primacy requirements for both the GWR and the RTCR. Also, EPA plans to develop guidance manuals specifically for small systems to help them comply with the RTCR. EPA is also working to update the Safe Drinking Water Information System (SDWIS) to include the requirements of the RTCR and have SDWIS ready in advance of the compliance date for the rule.

As discussed earlier, EPA believes that the treatment technique requirements are more protective of public health because they require a system to take preventive actions to address problems. This is a change from just issuing a PN and conducting additional monitoring under the 1989 TCR to proactively doing an assessment to determine the cause of the possible contamination under the RTCR and performing corrective action where needed.

C. Monitoring

1. Requirements

a. Requirements that apply to all PWSs.

As with the 1989 TCR, the RTCR requires all PWSs to collect and test samples for total coliforms and

E. coli

according to a sample siting plan and schedule specific to the system. PWSs must collect the samples at regular intervals throughout the month, except systems that use only ground water and serve 4,900 or fewer people may collect all required samples on a single day if they are taken from different sites.

Under the RTCR, all PWSs are still required to take repeat samples within 24 hours of learning of any routine monitoring sample that is total coliform-positive. PWSs must comply with the repeat monitoring requirements and

E. coli

analytical requirement, discussed in detail in section III.D of this preamble,

Repeat Samples.

All samples taken for RTCR compliance (routine and repeat) may occur at a customer's premises, dedicated sampling station, or other designated compliance sampling location.

EPA notes that a system must still take the required minimum number of samples even if it has had an

E. coli

MCL violation or has exceeded the coliform treatment triggers before the end of the monitoring compliance period. For example, if a system has an

E. coli

MCL violation after taking 10 of the 40 required routine monthly samples, the system must continue routine total coliform monitoring, analyze any total coliform-positive samples for

E. coli,

and take one round of repeat samples following any total coliform-positive routine sample.

Under the RTCR, systems' sample siting plans must include routine and repeat sample sites and any sampling points necessary to meet the Ground Water Rule (GWR) requirements. As with the 1989 TCR, the sample siting plan is subject to State review and revision.

The repeat sample sites may be alternative monitoring locations that the PWS is proposing to use instead of the repeat sample locations that are within five connections upstream and downstream of the original sampling location that tested total coliform-positive. The PWS must demonstrate to the State's satisfaction that the alternative monitoring locations are representative of a pathway for contamination into the distribution system (for example, near a storage tank), and that the sample siting plan remains representative of the water quality in the distribution system. Systems may elect to specify either alternative fixed locations or criteria for selecting their repeat sampling locations on a situational basis in a standard operating procedure (SOP), which is part of the sample siting plan. The State may determine that monitoring at the entry point to the distribution system (especially for undisinfected ground water systems) is effective to differentiate between potential source water and distribution problems. The use of alternative monitoring locations or an SOP does not require prior State approval but systems are required to submit to their primacy agencies their proposed alternative locations. States can modify and revise these locations or the SOP as needed. Additional discussion about the alternative monitoring locations can be found in section III.D of this preamble,

Repeat Samples

.

Monitoring locations that serve both as a repeat sampling location and a triggered source water monitoring location for the GWR (i.e., locations for dual purpose sampling) must also be included in the sample siting plan. These locations need to be approved by

the State before the PWS can use them. For more discussion on the dual purpose sampling, see section III.D of this preamble,

Repeat Samples.

Under the RTCR, PWSs may take more than the minimum required number of routine samples and must include the results in calculating whether the total coliform treatment technique trigger for conducting an assessment has been exceeded, but only if the samples are taken in accordance with the sample siting plan and are representative of water throughout the distribution system (see section III.E of this preamble,

Coliform Treatment Technique,

for a discussion on the coliform treatment technique requirements).

Under the RTCR, EPA is not making substantive changes to the requirements of the TCR for (1) special purpose samples, and (2) invalidation of total coliform samples.

New systems that begin operation on or after the compliance date of the RTCR must comply with the routine monitoring frequency established by the RTCR for their system size and type beginning in their first month of operation.

The following are the monitoring requirements for different categories of systems.

b. Ground water NCWSs serving ≤ 1,000 people

. i. Routine monitoring. The RTCR requires ground water NCWS serving 1,000 or fewer people to routinely monitor each quarter for total coliforms and

E. coli

except that systems can transition into RTCR at their 1989 TCR monitoring frequency as discussed in further detail in the next section, and there are provisions under which the monitoring frequency may be reduced or increased. Seasonal systems under this category must routinely monitor every month that they are in operation (see section III.C.1.f of this preamble,

Seasonal systems,

for additional discussion on seasonal system requirements).

ii. Transition to the RTCR. The RTCR requires all ground water NCWSs serving 1,000 or fewer people, including seasonal systems, to continue with their 1989 TCR monitoring schedules as of the compliance date of the RTCR, unless or until any of the conditions for increased monitoring discussed later in this section are triggered on or after the compliance date, or unless otherwise directed by the State as a result of the special monitoring evaluation conducted under a sanitary survey or at any other time the State believes that the sampling the system is conducting may not be adequate. In addition, systems on annual monitoring, including seasonal systems, must have an initial annual site visit by the State within one year of the compliance date and an annual site visit each calendar year thereafter to remain on annual monitoring. Systems may substitute a voluntary Level 2 assessment by a party approved by the State for the annual site visit in any given year. The periodic sanitary survey may be used to meet the requirement for an annual site visit for the year in which the sanitary survey was completed.

After the compliance date of the final RTCR, during each sanitary survey the State must perform a special monitoring evaluation to review the status of the water system, including the distribution system, to determine whether the system is on an appropriate RTCR monitoring schedule and modify the monitoring schedule as necessary. States must evaluate system factors such as the pertinent water quality and compliance history, the establishment and maintenance of contamination barriers, and other appropriate protections, and validate the appropriateness of the water system's existing RTCR monitoring schedule and modify as necessary. For seasonal systems on quarterly or annual monitoring, this evaluation must also include review of the approved sample siting plan, which designates the time period(s) for monitoring based on site-specific considerations (such as during periods of highest demand or highest vulnerability to contamination). The system must collect compliance samples during these designated time periods.

iii. Reduced monitoring. The State has the discretion to reduce the monitoring frequency for well-operated ground water NCWSs from the quarterly routine monitoring to no less than annual monitoring, if the water system can demonstrate that it meets the criteria for reduced monitoring provided in this section.

To be eligible to qualify for and remain on annual monitoring after the compliance date, a ground water NCWS serving 1,000 or fewer people must meet all of the following criteria:

• The system must have a clean compliance history (no MCL violations or monitoring violations under the 1989 TCR and/or RTCR, no Level 1 or Level 2 trigger exceedances or treatment technique violations under the RTCR) for a minimum of 12 months. (For a more detailed discussion on Level 1 and Level 2 triggers, see section III.E of this preamble,

Coliform Treatment Technique

);

• The most recent sanitary survey shows the system is free of sanitary defects, has a protected water source and meets approved construction standards; and

• An initial site visit by the State within the last 12 months to qualify for reduced annual monitoring, and recurring annual site visits to stay on reduced annual monitoring; and correction of all identified sanitary defects. A voluntary Level 2 assessment by a party approved by the State may be substituted for the State annual site visit in any given year.

iv. Increased monitoring. Ground water NCWS serving 1,000 or fewer people on quarterly or annual monitoring must begin monthly monitoring the month after any of the following events occurs:

• The system triggers a Level 2 assessment or two Level 1 assessments in a rolling 12 month period;

• The system has an

E. coli

MCL violation;

• The system has a coliform treatment technique violation (for example, if the system fails to conduct a Level 1 assessment or correct for sanitary defects if required to do so);

• The system on quarterly monitoring has two RTCR monitoring violations; or

• The system has one RTCR monitoring violation and triggers a Level 1 assessment in a rolling 12-month period.

EPA added the last condition by which a ground water NCWS serving ≤ 1,000 people can be triggered into increased monitoring to improve the internal consistency of these triggers, given that these NCWSs monitor less frequently in general, and given the added flexibility for States to elect not to count monitoring violations at TNCWS toward triggers to increased monitoring as described in the next paragraph. Since either two Level 1 assessments or two RTCR monitoring violations in a rolling 12-month period triggers increased monitoring, EPA believes it is appropriate for one of each of these events to also trigger increased monitoring for these NCWSs. See section III.E.1 of this preamble,

Coliform treatment technique triggers,

for a discussion of coliform treatment technique triggers.

EPA also added flexibility to allow States to elect to not count TNCWS monitoring violations in determining whether the trigger for increased monitoring has been exceeded, but only if the missed sample is collected no later than the end of the next monitoring period. The system must collect the make-up sample in a different week than the routine sample for the next monitoring period and should collect the sample as soon as possible during the next monitoring period. This

provision applies only for routine samples. The TNCWS would still incur a monitoring violation and must follow the other requirements associated with such violation (e.g., public notification and reporting). This provision is added in response to comments received by EPA. See section III.C.2.b of this preamble,

Ground water NCWSs serving ≤ 1,000 people,

for additional discussion of this provision.

Ground water NCWS serving 1,000 or fewer people on annual monitoring must begin quarterly monitoring the month after the following event occurs:

• The system on annual monitoring has one RTCR monitoring violation.

This is a change from the proposed rule requirement where the event would have triggered the system to go to monthly monitoring instead of quarterly monitoring. This change is further discussed in section III.C.2.b of this preamble,

Ground water NCWSs serving ≤ 1,000 people

.

The system must continue monthly or quarterly monitoring until the requirements in this section for returning to quarterly or annual monitoring are met.

v. Requirements for returning to quarterly monitoring. To be eligible to return from increased monthly monitoring to quarterly monitoring, ground water NCWSs serving 1,000 or fewer people must meet all of the following criteria:

• Within the last 12 months, the system must have a completed sanitary survey or a site visit by the State or a voluntary Level 2 assessment by a party approved by the State. The system is free of sanitary defects, and has a protected water source; and

• The system has a clean RTCR compliance history (no

E. coli

MCL violations, Level 1 or 2 triggers, coliform treatment technique violations or monitoring violations) for a minimum of 12 months.

For TNCWSs, the State may elect not to count monitoring violations towards the requirement of a clean compliance history (as presented in the last bullet) if the missed sample is collected no later than the end of the next monitoring period. This applies only for routine samples. The TNCWS would still incur a monitoring violation and must follow the other requirements associated with such violation (e.g., public notification and reporting). See section III.C.2.b of this preamble,

Ground water NCWSs serving ≤ 1,000 people,

for additional discussion about this provision.

vi. Requirements for returning to reduced annual monitoring. To be eligible to return from increased monthly monitoring to reduced annual monitoring, the system must meet the criteria to return to routine quarterly monitoring plus the following criteria:

• An annual site visit (recurring) by the State and correction of all identified sanitary defects. An annual voluntary Level 2 assessment may be substituted for the State annual site visit in any given year; and

• The system must have in place or adopt one or more additional enhancements to the water system barriers to contamination as approved by the State. These measures could include but are not limited to the following:

—Cross connection control, as approved by the State.

—An operator certified by an appropriate State certification program, which may include regular visits by a circuit rider certified by an appropriate State certification program.

—Continuous disinfection entering the distribution system and a residual in the distribution system in accordance with criteria specified by the State.

—Maintenance of at least a 4-log inactivation or removal of viruses each day of the month based on daily monitoring as specified in the GWR (with allowance for a 4-hour exception).

—Other equivalent enhancements to water system barriers to contamination as approved by the State.

vii. Additional routine monitoring. All systems collecting samples on a quarterly or annual frequency must conduct additional routine monitoring following a single total coliform-positive sample (with or without a Level 1 trigger event). The additional routine monitoring consists of three samples in the month following the total coliform-positive sample at routine monitoring locations identified in the sample siting plan. This is a change from the 1989 TCR additional routine monitoring requirement of taking a total of five samples the month following a total coliform-positive sample for systems that take four or fewer samples per month. Consistent with the 1989 TCR, the State may waive the additional routine monitoring requirement if:

• The State, or an agent approved by the State, performs a site visit before the end of the next month the system provides water to the public. Although a sanitary survey need not be performed, the site visit must be sufficiently detailed to allow the State to determine whether additional monitoring and/or any corrective action is needed. The State cannot approve an employee of the system to perform this site visit, even if the employee is an agent approved by the State to perform sanitary surveys or RTCR assessments.

• The State has determined why the sample was total coliform-positive and establishes that the system has corrected the problem or will correct the problem before the end of the next month the system serves water to the public. In this case, the State must document this decision to waive the following month's additional monitoring requirement in writing, have it approved and signed by the supervisor of the State official who recommends such a decision, and make this document available to the EPA and public. The written documentation must describe the specific cause of the total coliform-positive sample and what action the system has taken and/or will take to correct this problem.

• The State may not waive the requirement to collect three additional routine samples the next month in which the system provides water to the public solely on the grounds that all repeat samples are total coliform-negative. If the State determines that the system has corrected the contamination problem before the system takes the set of repeat samples required in § 141.858, and all repeat samples were total coliform-negative, the State may waive the requirement for additional routine monitoring the next month.

All additional routine samples are included in determining compliance with the MCL and coliform treatment technique requirements.

c. Ground water CWSs serving ≤ 1,000 people.

i. Routine monitoring. The RTCR requires ground water CWSs serving 1,000 or fewer people to routinely monitor at least once each month for total coliforms and

E. coli

except that systems can transition into RTCR at their 1989 TCR monitoring frequency as discussed in further detail in the next section, and there are provisions under which the sampling frequency may be reduced by the State.

The State may reduce the monitoring frequency for ground water CWS from the monthly routine monitoring to quarterly reduced monitoring if the water system can demonstrate that it meets the criteria for reduced monitoring provided later in this section.

ii. Transition to the RTCR. All ground water CWSs serving 1,000 or fewer people continue with their 1989 TCR monitoring schedules unless or until any of the increased monitoring requirements in this section occur or as directed by the State.

After the compliance date of the final RTCR, the State must determine

whether the system is on an appropriate monitoring schedule by performing a special monitoring evaluation during each sanitary survey to review the status of the PWS, including the distribution system. The first such evaluation must be conducted during the first scheduled sanitary survey after the effective date of the rule; a system may remain on its 1989 TCR monitoring schedule until this time unless it is triggered into more frequent monitoring. After its first evaluation, the State may allow the system to remain on its 1989 TCR monitoring schedule as long as the system meets the conditions for doing so. The State must evaluate system factors such as the pertinent water quality and compliance history, the establishment and maintenance of barriers to contamination, and other appropriate protections to validate the water system's existing monitoring schedule or require more frequent monitoring.

iii. Reduced monitoring. The State has the flexibility to reduce the monitoring frequency for well-operated ground water CWS from the monthly routine monitoring to no less than quarterly monitoring if the water system can demonstrate that it meets the criteria for reduced monitoring provided in this section.

To be eligible to change from monthly to quarterly reduced monitoring after the compliance date, ground water CWSs serving 1,000 or fewer people must be in compliance with any State-certified operator provisions and meet each of the following criteria:

• The system must have a clean compliance history (no MCL violations or monitoring violations under the TCR and/or RTCR, no Level 1 or Level 2 trigger exceedances or treatment technique violations under the RTCR) for a minimum of 12 months;

• The most recent sanitary survey shows the system is free of sanitary defects (or has an approved plan and schedule to correct them and is in compliance with the plan and the schedule), has a protected water source, and meets approved construction standards; and

• The system must meet at least one of the following criteria:

—An annual site visit by the State or an annual voluntary Level 2 assessment by a party approved by the State or meeting criteria established by the State and correction of all identified sanitary defects (or an approved plan and schedule to correct them and is in compliance with the plan and schedule).

—A cross connection control program, as approved by the State.

—Continuous disinfection entering the distribution system and a residual in the distribution system in accordance with criteria specified by the State.

—Demonstration of maintenance of at least a 4-log inactivation or removal of viruses each day of the month based on daily monitoring as specified in the GWR (with allowance for a 4-hour exception) (USEPA 2006c, 71 FR 65574, November 8, 2006).

—Other equivalent enhancements to water system barriers to contamination as approved by the State.

iv. Requirements for returning to monthly monitoring. When a system on quarterly monitoring experiences any of the following events the system must begin monthly monitoring the month after the event occurs:

• System triggers a Level 2 assessment or two Level 1 assessments in a rolling 12-month period.

• System has an

E. coli

MCL violation.

• System has a coliform treatment technique violation (e.g., fails to conduct a Level 1 or Level 2 assessment or to correct for a sanitary defect if required to do so).

• System has two routine RTCR monitoring violations in a rolling 12-month period.

The system must continue monthly monitoring until all the reduced monitoring requirements discussed previously in this section are met. A system that loses its certified operator must also return to monthly monitoring the month following the loss.

v. Additional routine monitoring. Ground water CWSs serving ≤ 1,000 people collecting samples on a quarterly frequency must conduct additional routine monitoring following a single total coliform-positive sample (with or without a Level 1 trigger event), similar to the additional monitoring requirements for ground water NCWS serving ≤ 1,000 people. See section III.C.1.b.vii of this preamble,

Additional routine monitoring,

for a discussion of the additional routine monitoring requirements.

d. Subpart H systems serving ≤ 1,000 people.

The monitoring requirements for subpart H systems of this part (PWSs supplied by a surface water source or by a ground water under the direct influence of surface water (GWUDI) source) serving 1,000 or fewer people remain the same as under the 1989 TCR (see § 141.856). These systems are not eligible for reduced monitoring. In addition, the rule requires all seasonal systems, on and after the compliance date of the final RTCR, to demonstrate completion of a State-approved start-up procedure (see section III.C.1.f of this preamble,

Seasonal systems,

for additional discussion on seasonal system requirements).

e. PWSs serving > 1,000 people.

The monitoring requirements for PWSs serving more than 1,000 people remain the same as under the 1989 TCR (see § 141.857), with the exception of the applicable revisions to the repeat sampling locations provided in § 141.858 and to the additional routine monitoring provisions. Systems on monthly monitoring are not required to take additional routine samples the month following a total coliform-positive sample, as recommended by the advisory committee (see section III.A.3.b.ii(g) of the preamble to the proposed RTCR,

Additional routine monitoring,

for an explanation of this change from the 1989 TCR). Consistent with the 1989 TCR, systems serving > 1,000 people are not eligible for reduced monitoring. In addition, the rule requires all seasonal systems, on and after the compliance date of the final RTCR, to demonstrate completion of a State-approved start-up procedure (see section III.C.1.f of this preamble,

Seasonal systems,

for additional discussion on seasonal system requirements).

f. Seasonal systems.

Since seasonal systems are a subset of NCWSs, they are subject to the requirements of the particular NCWS size category they fall under (e.g., seasonal systems using ground water and serving ≤ 1,000 people are subject to the requirements of ground water NCWS serving ≤ 1,000 people, or seasonal systems using surface water and serving ≤ 1,000 people are subject to the requirements of subpart H systems serving ≤ 1,000 people, and so on), unless otherwise noted. The RTCR is promulgating requirements specific to seasonal systems to mitigate the risk associated with the unique characteristics of this type of systems (see section III.A.4 of this preamble,

Seasonal systems,

for additional discussion about seasonal systems). One of the provisions is the requirement that all seasonal systems must demonstrate completion of a State-approved start-up procedure prior to serving water to the public on and after the compliance date of the final RTCR each time they start up the system. The start-up procedure may include a requirement for a start-up sample prior to serving water to the public.

Under the RTCR, all seasonal systems are required to take at least one routine sample per month for total coliforms and

E. coli

during the months that they are in operation, unless the sampling

frequency has been reduced by the State under the RTCR. Seasonal systems serving > 1,000 people have the same monitoring frequency as other PWSs serving > 1,000 people (see § 141.857 of the RTCR) and it cannot be reduced. However, seasonal systems serving ≤ 1,000 people that are not on monthly monitoring by the compliance date of the RTCR may continue with their existing 1989 TCR monitoring frequency afterwards, unless or until any of the conditions for increased monitoring discussed previously in section III.C.1.b.iv of this preamble,

Increased monitoring,

are triggered on or after the compliance date, or as directed by the State. To continue on their existing 1989 TCR monitoring frequency, seasonal systems on less than monthly monitoring at the compliance date of the RTCR must have an approved sample siting plan that designates the time period for monitoring based on site-specific considerations (e.g., during periods of highest demand or highest vulnerability to contamination). The system must collect compliance samples during this time period. Seasonal systems on annual monitoring frequency are required to have a recurring annual site visit by the State (or an annual voluntary Level 2 assessment by a party approved by the State) to remain on annual monitoring.

Only seasonal systems using ground water and serving ≤ 1,000 people are eligible for reduced monitoring. To be newly eligible for reduced monitoring after the compliance date, they must meet the following criteria:

• The system must have an approved sample siting plan that designates the time period for monitoring based on site-specific considerations (e.g., during periods of highest demand or highest vulnerability to contamination). The system must collect compliance samples during this time period; and

• To be eligible for reduced quarterly monitoring, the system must also meet all the reduced monitoring criteria discussed in section III.C.1.b.v of this preamble,

Requirements for returning to quarterly monitoring,

and provided in § 141.854(g) of the RTCR.

• To be eligible for reduced annual monitoring, the system must also meet all the reduced monitoring criteria discussed in section III.C.1.b.vi of this preamble,

Requirements for returning to reduced annual monitoring,

and provided in § 141.854(h) of the RTCR.

The State may exempt any seasonal system from some or all of the requirements for seasonal systems (e.g., performing start-up procedures) if the entire distribution system remains pressurized during the entire period that the system is not operating. However, systems that monitor less frequently than monthly must still monitor during the time period designated in their approved sample siting plan.

g. Consecutive systems.

EPA did not identify any issues regarding consecutive systems in the RTCR. Consecutive systems must monitor for total coliforms at a frequency based on the population served by the consecutive system and the source water type of the wholesale system. In instances where it is justified to treat two or more distribution systems as a single system for monitoring purposes, 40 CFR 141.29 allows the State to modify the monitoring requirements for the combined distribution system. Any modifications to the monitoring requirements must be approved by EPA. The State may not, however, modify the compliance requirements. The RTCR is not modifying the provisions of 40 CFR 141.29. When conducting assessment and corrective action under the RTCR, wholesalers and consecutive systems should cooperate as directed by the State and conduct assessment and corrective action based on the location of the positive sample results, the potential pathways of distribution system contamination, and the sanitary defects identified.

2. Key Issues Raised

a. Sample siting plans.

The majority of the comments EPA received supported the proposal that sample siting plans be subject to State review and revision instead of requiring State approval. The advisory committee recommended that States review and revise sample siting plans consistent with current practice and that the State develops and implements a process to ensure the adequacy of sample siting plans. EPA also received comments that requiring State approval of sample siting plans will be an additional burden to the States. Considering these comments and the recommendation of the advisory committee, EPA, therefore, is not changing the requirement regarding State review and revision of the sample siting plan in most instances. There are, however, instances where it is necessary for the State to review and approve elements of the sample siting plan, and other instances where the need for State approval is left to State discretion. For example, seasonal systems on less than monthly monitoring must have an approved sample siting plan that designates the time period for collecting the sample(s) as discussed previously in section III.C.1.f of this preamble,

Seasonal systems.

On the other hand, for systems that want to establish repeat sampling locations other than the within-five-connections-upstream-and-downstream of the total coliform-positive sample, the system must submit the siting plan for review and the State may modify the sampling locations as needed, but State approval is not required by the RTCR, as discussed in section III.D of this preamble,

Repeat Samples.

EPA received comment that supported the use of dedicated sampling locations. Although not specifically addressed this practice is already in use by some States and systems under the 1989 TCR. As discussed in the proposed RTCR, EPA is specifically allowing the use of dedicated sampling stations for the following reasons:

• To reduce potential contamination of the sampling taps. Utilities will have more control to prevent contamination of the sampling tap by preventing its use by unauthorized persons and allowing no routine use of the tap except for sampling.

• To facilitate access to sampling taps. Currently systems may be constrained by where they sample, e.g., only at public buildings or in certain individual customer's house.

• To improve sampling representation of the distribution system. Allowing dedicated sampling taps in areas where systems have not been able to gain access will facilitate better sampling representation of the distribution system.

b. Ground water NCWSs serving ≤ 1,000 people.

EPA received comments regarding the monitoring requirements for small ground water NCWSs. Many of the commenters agreed with the requirements proposed while some commenters suggested that systems should not be allowed to monitor less than monthly.

The advisory committee recommended that the routine monitoring frequency for ground water NCWSs serving 1,000 or fewer people remain at quarterly monitoring as provided in the 1989 TCR. EPA believes that quarterly monitoring carried out in conjunction with the assessment and corrective action requirements would maintain or improve public health protection without increasing sampling costs over the 1989 TCR requirements. The advisory committee also recognized that current sampling costs are not insignificant for small systems, and wanted to allow reduced monitoring for well-performing systems under the more specific and rigorous criteria described previously in sections III.C.1.b.iii,

Reduced monitoring,

and III.C.1.c.iii,

Reduced monitoring,

of this preamble. To continue to provide adequate health

protection, systems on reduced monitoring must adhere to criteria that ensure that barriers are in place and are effective. Furthermore, systems with problems that may indicate poor system integrity, maintenance, or operations, or systems that fail to monitor, are triggered into more frequent monitoring. This approach leverages the limited resources of small ground water NCWSs and of States, so that well-operated systems can minimize their costs and States can focus their resources on systems needing the greatest attention, such as systems with problems or vulnerabilities.

EPA requested comment in the proposed rule on whether to require NTNCWSs to comply with the CWS requirements (as they are in other rules such as disinfection byproduct (DBP) rules) since NTNCWSs serve the same people over time and include populations that may be at greater risk (e.g., schools, hospitals, daycare centers).

EPA received comments both in agreement and disagreement with this approach. Those who disagreed stated that such requirement would result in disproportionate impact on NTNCWS, since these systems are small systems with limited resources. One commenter said that the 1989 TCR has been in effect for decades now and there have been no adverse health effect impacts by not having NTNCWSs comply with CWS requirements.

Considering the comments EPA received, the Agency is not requiring NTNCWSs to comply with CWS requirements under the RTCR. However, EPA recommends that States consider the population served at NTNCWSs, especially those that serve sensitive subpopulations such as schools, hospitals, and daycare centers, when they decide on an appropriate monitoring frequency. EPA is aware that some States are already doing so and suggests that other States consider the same.

EPA received comments that the criteria for returning to reduced monitoring are overly strict, including a suggestion that the requirement to have an additional barrier enhancement to return to annual monitoring is too burdensome and costly. Some commenters stated that systems that are triggered into increased monitoring will be unlikely to return to reduced monitoring. Another commenter suggested that a system should be able to return to reduced monitoring sooner than 12 months.

EPA continues to believe that for a system to be able to monitor only once a year, it should be able to demonstrate that it has the ability to continually deliver safe water by ensuring that barriers are in place to protect against contamination. A system that has been triggered into increased monitoring has failed in some way to demonstrate that it has those barriers in place. The requirements to return to reduced monitoring are intended to show that the system has made the long-term commitment and provided the necessary additional barriers to eliminate the vulnerability to contamination that triggered the increased monitoring in the first place. EPA believes that the requirements for returning to reduced monitoring are not impossible to meet but require an appropriate level of effort over at least 12 months to show the commitment and ability to deliver safe water.

EPA received comments regarding monitoring violations as a trigger for increased monitoring and as part of the criteria for returning to reduced monitoring. EPA heard from States with large numbers of NCWSs that including monitoring violations as a trigger for increased monitoring and as part of the criteria for reduced monitoring will make the RTCR difficult to implement in their States. NCWSs, especially TNCWSs, pose unique challenges to rule compliance as they typically do not have the resources that CWSs have and providing water is not their primary business. Commenters suggested that triggering a NCWS into increased monitoring because of just one or two missed samples is not appropriate and will burden the State with compliance and enforcement tracking. They indicated that this will shift limited State resources away from oversight activities for CWSs that serve large populations to compliance and enforcement activities for NCWSs that serve small populations, resulting in decreases in public health protection. The commenters also concluded that once a system is triggered into increased monitoring, it would not be able to qualify for reduced monitoring because it would not be able to meet the requirements for clean compliance history (e.g., no monitoring violations).

EPA recognizes the burden on States that may result from implementing the increased and reduced monitoring provisions of the RTCR. EPA is therefore providing States the flexibility to not count monitoring violations towards eligibility for remaining on quarterly monitoring or for returning to quarterly monitoring as long as a make-up sample is collected by the end of the next monitoring period. This flexibility only applies to TNCWSs and only for routine samples. The State cannot use this flexibility to qualify a system for annual monitoring. When exercising the flexibility about whether to count a monitoring violation towards eligibility for reduced monitoring, the State may find it appropriate to also consider the system's history of monitoring violations. The TNCWSs would still incur a monitoring violation and must comply with the other associated requirements after such violation (e.g., public notification and reporting).

In the proposed rule, a NCWS on annual monitoring with one RTCR monitoring violation is triggered into monthly monitoring. Some commenters expressed concern that many systems on annual monitoring will be triggered to monthly monitoring because of just one missed sample. The commenters stated that this was unreasonable considering that these systems typically do not have the resources that CWSs have, such as a certified operator. These systems typically experience frequent staff shortages or turnover that result in missed samples. Having these systems do monthly monitoring would require significant tracking and enforcement activities on the part of the State.

To address this concern, EPA has changed the consequence of having one RTCR monitoring violation for systems on annual monitoring. Instead of having to go to monthly monitoring, the system now moves to quarterly monitoring. EPA also believes that the annual site visit by the State, and the fact that some States conduct and/or pay for the annual monitoring, reduces the likelihood that systems on annual monitoring will miss samples and be triggered to increase to quarterly monitoring, so that PWS and State resource needs are not likely to significantly increase because of this requirement. EPA is not changing the consequence of exceeding the other triggers for increased monitoring; systems that experienced any of the other events in section III.C.1.b.iv of this preamble,

Increased monitoring,

will need to monitor monthly instead of quarterly. Systems can go back to annual monitoring by meeting the criteria for reduced monitoring.

EPA requested comment on whether daily chlorine residual measurements should be one of the criteria for reduced monitoring. EPA received comments that said that it should not be a criterion. Some commenters expressed concern that one missed measurement might be a basis for being bumped to increased monitoring. One commenter suggested giving the State the discretion to either allow or not allow it as a criterion. Section 141.854(h)(2)(iii) of the RTCR specifies that one of the

enhancements to water system barriers to contamination is continuous disinfection entering the distribution system and a residual in the distribution system in accordance with criteria specified by the State. States are given the discretion to decide how they want to implement this criterion based on site-specific considerations. States may want to require daily measurement of chlorine residual to demonstrate continuous disinfection.

One commenter expressed concern that a reduction in the number of additional routine samples (i.e., from five to three) reduces the likelihood of detecting both total coliforms and

E. coli.

The advisory committee recommended that it is appropriate to drop from five to three samples the following month to reduce monitoring costs while still maintaining a substantial likelihood of identifying a problem if a problem persists. EPA and the advisory committee recognized that a reduction in the number of samples taken could also mean a reduction in the number of positive samples found. However, EPA and the advisory committee concluded that the new assessment and corrective action provisions of the RTCR lead to a rule that is more protective of public health and to improvement in water quality despite the reductions in the number of samples taken. The Final RTCR EA occurrence modeling results support this conclusion, as they predict that more

E. coli

MCL violations will be prevented and total coliform and

E. coli

-positive hit rates will decrease when assessment and corrective action occur. See chapter 6 of the Final RTCR EA (USEPA 2012a) for more details.

c. Seasonal systems.

EPA received comments that disagreed with the routine monthly monitoring frequency for seasonal systems. The commenters suggested that requiring a start-up procedure is the essential element and having seasonal systems monitor quarterly like all other NCWSs should be adequate. Other commenters agreed with monthly monitoring.

As discussed in section III.A.4 of this preamble,

Seasonal systems,

seasonal systems are more susceptible to contamination due to changes in the conditions of the source water during the period the system is in operation. Such changes include variable contaminant loading due to increased septic tank or septic field use, the seasonal nature of the demand, and the stress the system may experience. Because of the risk factors, the advisory committee decided that more frequent monitoring is appropriate for these systems, with the possibility of going on reduced monitoring if they meet certain criteria. EPA concurs with the advisory committee assessment and the final rule maintains the proposed routine monthly monitoring frequency, when they are in operation, for seasonal systems.

One commenter said that a regular sampling schedule is more easily achieved and more practical than identifying vulnerable time periods as these periods can vary from year to year. EPA believes that a system that will monitor less frequently than monthly should sample based on site-specific considerations (e.g., during periods of high demand or highest vulnerability of contamination). This increases the probability of detecting a possible contamination; hence, measures can be taken to address the possible contamination before it becomes a public health threat.

One commenter suggested that start-up procedures must include flushing, disinfection, re-flushing to eliminate disinfectant residual, and taking a sample prior to serving water to the public. EPA is not requiring specific practices regarding the start-up procedure. States are given the flexibility to determine what start-up procedures are appropriate for a particular system based on its site-specific considerations and must describe their process for determining start-up procedures in their primacy application. EPA recommends that States require seasonal systems to take a sample as part of the required start-up procedures. Systems must allow sufficient time for completing start-up procedures (including receiving sample results) and notifying the State as required prior to serving water to the public.

D. Repeat Samples

1. Requirements

Under the RTCR, all PWSs must take at least three repeat samples for each routine sample that tested positive for total coliforms. This is a change from the 1989 TCR requirements where systems serving 1,000 or fewer people must collect at least four repeat samples while the rest of the systems must collect three repeat samples.

As discussed in the preamble to the proposed RTCR, EPA believes that sampling again immediately after determining that a sample is positive (i.e., conducting repeat sampling) increases the likelihood of identifying the source and/or nature of the possible contamination. Analyses conducted by EPA indicated that once a total coliform-positive is found, there is a much greater likelihood of finding another total coliform-positive within a short period of time of the initial finding (see page 40939 of the

Federal Register

(FR) notice for the proposed RTCR (USEPA 2010a, 75 FR 40926, July 14, 2010) for more discussion on the analyses done by EPA regarding repeat samples). Repeat sampling (when it is total coliform-positive) can indicate a current pathway for potential external contamination into the distribution system. EPA recommends that States work with PWSs and laboratories to facilitate timely notification through the most expeditious method (e.g., phone, fax, or email) to ensure that repeat samples are taken in a timely manner.

The repeat monitoring requirements of the RTCR are essentially the same as the requirements of the 1989 TCR, except for some new provisions promulgated by the RTCR to provide flexibility to States and PWSs. The following requirements are not changing under the RTCR:

• PWSs must collect the repeat samples within 24-hours of being notified that their routine sample is total coliform-positive.

• The State can extend the 24-hour limit on a case-by-case basis. EPA is providing flexibility to this provision as discussed later in this section.

• The State cannot waive the requirement for a system to collect repeat samples.

• In addition to taking repeat samples, PWSs must test each routine total coliform-positive sample for

E. coli.

They must also test any repeat total coliform-positive sample for

E. coli.

If

E. coli

is present, the system must notify the State the same day it learns of the positive result, or by the end of the next business day if the State office is closed and the State does not have either an after-hours phone line or an alternative notification procedure.

• The State has the discretion to allow the system to forgo

E. coli

testing in cases where the system assumes that the total coliform-positive sample is

E. coli

-positive. If the State allows a system to forgo

E. coli

testing, the system must still notify the State and comply with the

E. coli

MCL requirements specified in § 141.858.

• The system must collect at least one repeat sample from the sampling tap where the original total coliform-positive sample was taken. Unless different locations are specified in its sample siting plan (this is a new provision of the RTCR and is discussed later in this section), the system must also collect at least one repeat sample at a tap within five service connections upstream, and at least one repeat sample at a tap within five service connections

downstream of the original sampling site. The State may waive the requirement to collect at least one repeat sample upstream or downstream of the original sampling site if the total coliform-positive sample is at the end of the distribution system, or one service connection away from the end of the distribution system. EPA notes that it is the location of the repeat sample that is waived, not the required number of repeat samples. A PWS still needs to take the required repeat sample(s) elsewhere in the distribution system if it is unable to do so upstream or downstream of the original sampling site.

• Systems must collect all repeat samples on the same day. The State may allow systems with a single service connection to collect the required set of repeat samples over a three-day period or to collect a larger volume repeat sample(s) in one or more sample containers of any size, as long as the total volume collected is at least 300 milliliters (ml).

• Systems must collect an additional set of repeat samples for each total coliform-positive repeat sample. As with the original set of repeat samples, the system must collect the additional repeat samples within 24 hours of being notified of the positive result, unless the State extends the time limit. The system must repeat this process until either total coliforms are not detected in one complete set of repeat samples or, as the RTCR is adding, the system determines that the coliform treatment technique trigger has been exceeded and notifies the State. After a trigger (see section III.E, of this preamble,

Coliform Treatment Technique

) is reached, the system is required to conduct only one round of repeat monitoring after each total coliform-positive or

E. coli-

positive routine sample. If a trigger is reached as a result of a repeat sample being total coliform- or

E. coli

-positive, no further repeat monitoring related to that sample is necessary.

• A subsequent routine sample, which is within five service connections of the initial routine sample and is collected after an initial routine sample but before the system learns the initial routine sample is total coliform-positive, may count as a repeat sample instead.

• A ground water system with a single well serving 1,000 or fewer people may still use a repeat sample collected from a ground water source to meet both the repeat monitoring requirements of the RTCR and the triggered source monitoring requirements of the GWR (i.e., a dual purpose sample). Modifications to this provision under the RTCR are discussed later in this section.

As mentioned previously, the RTCR adds some new provisions to the repeat monitoring requirements to provide flexibility to the States and PWSs. One of these changes is the additional flexibility provided to States regarding the waiver or the extension of the 24-hour limit for a PWS to collect repeat samples. States are given the option to describe in their primacy application the criteria they will use to waive or extend the 24-hour limit instead of making the decisions on a case-by-case basis. This is discussed further in section V of this preamble,

State Implementation.

Another change is the use of alternative monitoring locations. As discussed in section III.C of this preamble,

Monitoring,

the PWS may propose alternative repeat monitoring locations that are expected to better characterize or identify pathways of contamination into the distribution system. Systems may elect to specify either alternative fixed locations or criteria for selecting their repeat sampling locations on a situational basis in a standard operating procedure (SOP), which is part of the sample siting plan. By allowing systems to specify criteria for selecting their repeat sampling locations in their SOP instead of setting fixed repeat sampling locations, systems can provide a more flexible and more protective response. The system can focus the repeat samples at locations that will best verify and determine the extent of potential contamination of the distribution system based on specific situations. For discussion on additional requirements for alternative monitoring locations, see section III.C of this preamble,

Monitoring.

There are also some modifications to the dual purpose sampling allowed under the GWR and 1989 TCR. Ground water systems required to conduct triggered source monitoring under the GWR must take ground water source samples in addition to the repeat samples required by the RTCR. However, a ground water system serving 1,000 or fewer people may use a repeat sample collected from a ground water source to meet both the repeat monitoring requirements of the RTCR and the source water monitoring requirements of the GWR (i.e., a dual purpose sample), but only if the State approves the use of a single sample to meet both rule requirements and the use of

E. coli

as a fecal indicator for source water monitoring. If the sample is

E. coli

-positive, the system violates the

E. coli

MCL under the RTCR and must also comply with the GWR requirements following a fecal indicator-positive sample. These provisions are consistent with the GWR.

If a system with a limited number of monitoring locations (such as a system with only one service connection or a campground with only one tap) takes more than one repeat sample at the triggered source water monitoring location, the system may reduce the number of additional source water samples by the number of repeat samples taken at that location that were not

E. coli

-positive. For example, if a system takes two dual purpose samples and one is

E. coli-

positive and the other is

E. coli

-negative, the system has an

E. coli

MCL violation under the RTCR and is required to take four additional source water samples, rather than five, under the GWR (see 40 CFR 141.402(a)(3)). If the system takes more than one of these repeat samples at the triggered source water monitoring location and has more than one repeat sample that is

E. coli

-positive at the triggered source water monitoring location, then the system would have both an

E. coli

MCL violation under the RTCR and a second fecal indicator-positive source sample under the GWR. The system would then need to also comply with the GWR treatment technique requirements under 40 CFR 141.403.

Results of all routine and repeat samples not invalidated by the State must be used to determine whether the coliform treatment technique trigger has been exceeded (see section III.E of this preamble,

Coliform Treatment Technique,

for a discussion of the coliform treatment technique triggers).

2. Key Issues Raised

A majority of the commenters supported the change from four to three repeat samples for systems serving 1,000 or fewer people. However, one commenter stated that decreasing the number of repeat samples would also lessen the likelihood of detecting total coliforms and

E. coli.

EPA explained the analysis that EPA has done to support the reduction in the number of repeat samples in the preamble to the proposed RTCR. In that analysis, using the Six-Year Review 2 data (USEPA 2010c), EPA showed that if the number of required repeats were reduced from four to three, there would still be almost as many (approximately 94 percent) situations leading to an assessment being triggered for the system. See section III.A.4 of the preamble to the proposed RTCR,

Repeat Samples,

for a detailed discussion of EPA's analysis on the reduction of the number of repeat

samples. Although dropping the required number of repeat samples from four to three means that some fraction of triggered assessments may be missed, the other provisions of the RTCR compensate for that change and, taken as a whole, the provisions of the RTCR provide for greater protection of public health. One such provision includes enhanced consequences for monitoring violations. For example, systems that do not take all of their repeat samples under the RTCR are triggered to conduct a Level 1 assessment. This permits an increase in public health protection over the 1989 TCR because PWSs are required to assess their systems when lack of required monitoring creates a situation where the PWS does not properly know whether it is vulnerable to contamination. Moreover, because of the substantial cost of this potential consequence, systems would be more likely to take all of their required repeat samples in the first place (see section III.E of this preamble,

Coliform Treatment Technique,

for additional discussion on the coliform treatment technique triggers).

EPA also received comments generally supporting the use of alternative sites for repeat monitoring since they provide more flexibility in determining the locations of the repeat samples, allowing for better protection of public health on a site-specific basis, subject to State review. One commenter disagreed, saying that repeat samples should be near the original positive sample site so that they can provide the necessary information to confirm the original positive sample. A few commenters are against having within-five-connections-upstream-and-downstream locations from the original positive sample as the default locations for repeat monitoring. They suggested that these default locations should be eliminated altogether and that all PWSs be allowed to take the other two repeat samples at alternative locations.

EPA believes that not all systems will use the option of taking repeat samples at alternative locations. Some PWSs, especially small NCWSs, may not avail themselves of this option for reasons of simplicity and lack of resources and expertise. They may elect to stick with the set repeat monitoring locations of five connections upstream and downstream of the original total coliform-positive sample, as it will be less burdensome on them than locating alternative sites and demonstrating that the alternative sites are more effective. Hence, EPA is maintaining within-five-connections-upstream-and-downstream locations as the default repeat sampling locations.

While the prescribed locations may work for some systems, other systems may find them too limiting. Taking repeat samples at the prescribed locations of within five-connections-upstream-and-downstream can be difficult for some systems to implement within the required 24 hours for a repeat sample because of issues such as access to the site. Therefore, EPA is allowing PWSs to propose alternative repeat monitoring locations, either as fixed locations or as criteria in an SOP, to facilitate the identification of the source and extent of any problem. EPA believes that both the within-five-connections-upstream-and-downstream repeat sampling locations and the locations as identified by an SOP can be used by the operator to better understand the extent and duration of potential pathways of contamination into the distribution system with the appropriate amount of State supervision.

EPA requested comment on whether systems should be required to obtain prior State approval for using repeat monitoring sites other than the within-five-connections-upstream-and-downstream locations of the original routine total coliform-positive site. Most of the commenters were against requiring prior State approval for the use of alternative repeat monitoring locations. They suggested that it is more appropriate to include these sites (or the criteria to choose sites) in the SOP or in the sample siting plan, which is then subject to State review and revision. Some commenters also stated that requiring pre-approval for each individual instance of using alternative sites is not practical.

EPA agrees that obtaining prior State approval to use alternative repeat monitoring locations is not necessary since there is no reduction in monitoring and EPA expects the SOP to be used only by large systems with the technical resources to justify alternative monitoring sites. Although State approval is not required, EPA requires PWSs that are intending to use this option to submit their proposed alternative sampling sites (as part of an SOP or the sample siting plan) to the State. The PWS must be able to demonstrate to the State that the alternative monitoring sites are appropriate to help characterize the extent of the possible contamination. The State is given the discretion to review and revise the alternative monitoring locations consistent with their practice regarding sample siting plans. EPA does not require that the State formally acknowledge and approve the alternative monitoring locations. The alternative monitoring locations are considered appropriate unless the State disapproves or modifies them, which results in the requirement being self-implementing.

EPA received general support for allowing samples taken at the ground water source to serve both as a triggered source sample under the GWR and as one of the repeat samples under the RTCR (i.e., as dual purpose samples). Some States said that this practice is already being done in their States and therefore should continue under the RTCR. Most commenters supported the provision with the understanding that the practice would be subject to State approval. One commenter, however, disagreed with the provision and thought the PWS would not be collecting a sufficient number of repeat samples to represent the water quality in the distribution system if one of the repeat samples is taken at the source water. Another commenter suggested making the option available for ground water systems of all sizes, as it will help reduce labor and analytical costs, and will provide a clearer picture as to the location and cause of the total coliform-positive sample.

The preamble to the proposed RTCR discussed the drawbacks to allowing dual purpose samples i.e., a reduction in the number of repeats in the distribution system. By requiring State approval of the use of dual purpose sampling, the RTCR ensures that this flexibility will only be allowed where the State has determined it is appropriate. EPA believes that PWSs with limited or no distribution systems are the best candidates for approval since there is little to no chance of contamination from the distribution system except from cross connection. On the other hand, EPA believes that dual purpose samples may not be appropriate for systems with extensive distribution systems because the reduction in monitoring (i.e., one less repeat sample in a distribution system that extends far from the source water sample site) may not provide public health protection equivalent to taking separate samples.

EPA requested comment on whether the use of dual purpose samples should be allowed by simply including it in the sample siting plan, without prior State approval. As stated earlier, most of the comments supported allowing dual purpose sampling with the understanding that it will be approved by the State. Some commenters, on the other hand, said that it should be allowed without prior State approval. One commenter said that the State may not be able to review and approve the sample siting plan until the next

sanitary survey, which maybe as long as five years after the RTCR implementation. One commenter said that States should only be required to say that dual purpose sampling is not allowed for specific systems. Another commenter suggested allowing States to explain their process for approval in their primacy application, rather than each situation being handled on a case-by-case basis, thereby reducing administrative burden.

As discussed earlier, EPA believes that requiring State approval for allowing dual purpose sampling limits the practice only to systems that can avail themselves of it without compromising public health protection. State approval is required because this constitutes a reduction in monitoring (no separate triggered source water samples), relative to requiring separate samples for compliance with the two rules. EPA believes this reduction in monitoring is appropriate only if the State determines that the dual purpose sample provides public health protection equivalent to that provided by separate repeat and source water samples.

As part of the special primacy requirements for the RTCR in § 142.16(q), States adopting the reduced monitoring provisions of the RTCR, including dual purpose sampling, must describe how they will do so in their primacy application package. States must include their approval process for dual purpose sampling in their application. This gives States the flexibility to determine how and when they want to grant approval, i.e., whether on a case-by-case basis (whenever a total coliform-positive occurs) or on a pre-approved basis (i.e., the system has prior State approval to take a dual purpose sample whenever it is triggered to do source water monitoring).

E. Coliform Treatment Technique

1. Coliform Treatment Technique Triggers

a. Requirements.

The non-acute MCL violation for total coliforms under the 1989 TCR is replaced under the RTCR by a coliform treatment technique involving monitoring for total coliforms and assessment and corrective action when triggered. EPA is establishing an assessment process in the RTCR to strengthen public health protection. Under the 1989 TCR, a system is not required to perform an assessment following a monthly/non-acute MCL violation or an acute MCL violation. Under the RTCR treatment technique framework, the presence of total coliforms is used as an indicator of a potential pathway of contamination into the distribution system. As discussed in section III.B of this preamble,

Rule Construct: MCLG and MCL for E. coli and Coliform Treatment Technique,

the RTCR eliminates the associated MCLG and MCL for total coliforms. The RTCR specifies two levels of treatment technique triggers, Level 1 and Level 2, and their corresponding levels of response. The degree and depth to which a PWS must examine its system and monitoring and operational practices, i.e., the difference between a Level 1 or Level 2 assessment, depends on the degree of potential pathway for contamination. A Level 2 assessment requires a more in-depth and comprehensive review of the PWS compared to a Level 1. A discussion of the levels of assessments is found later in section III.E.2 of this preamble,

Assessment.

The system has exceeded the trigger immediately once any of the following conditions have been met.

Level 1 treatment technique triggers

• For systems taking 40 or more samples per month, the PWS exceeds 5.0 percent total coliform-positive samples for the month; or

• For systems taking fewer than 40 samples per month, the PWS has two or more total coliform-positive samples in the same month; or

• The PWS fails to take every required repeat sample after any single routine total coliform-positive sample.

The first two treatment technique triggers were the conditions that define a non-acute MCL violation under the 1989 TCR. The third trigger provides incentive for systems to take their repeat samples to ensure that they are assessing the extent of the total coliform contamination; if they do not do so by repeat sampling, they must conduct an assessment instead to ensure there are no pathways to contamination (sanitary defects). Repeat monitoring is critical in identifying the extent, source, and characteristics of fecal contamination in a timely manner. EPA's analysis, as discussed in the preamble to the proposed RTCR (see section III.A.4 of the preamble to the proposed RTCR,

Repeat samples),

shows that the average percentage of repeat samples that are positive is much higher than that of routine samples, demonstrating that when operators are required to take a second look at their systems following the positive routine sample, they find, on average, a higher rate of coliform presence than during routine sampling. In other words, the high repeat total coliform positive rate indicates the persistence of total coliforms at such locations in the distribution system. Since under the RTCR there is no additional routine monitoring for systems that monitor at least monthly and the number of additional routine monitoring and repeat monitoring samples for the smallest systems that are not on monthly monitoring is decreased, the need to conduct repeat monitoring is more crucial than ever in providing immediate and useful information needed to protect public health.

Level 2 treatment technique triggers:

• The PWS has an

E. coli

MCL violation (see section III.F of this preamble,

Violations,

for a description of what constitutes an

E. coli

MCL violation); or

• The PWS has a second Level 1 treatment technique trigger within a rolling 12-month period, unless the initial Level 1 treatment technique trigger was based on exceeding the allowable number of total coliform-positive samples, the State has determined a likely reason for the total coliform-positive samples that caused the initial Level 1 treatment technique trigger, and the State establishes that the system has fully corrected the problem; or

• For PWSs with approved reduced annual monitoring, the system has a Level 1 treatment technique trigger in two consecutive years.

b. Key issues raised.

EPA received comments that disagreed with the inclusion of the third Level 1 treatment technique trigger, i.e., failing to take every required repeat sample after any single routine total coliform-positive sample triggers a Level 1 assessment. Some of the commenters suggested that this does not pose a public health concern and should remain a monitoring violation because if a system does not conduct the required repeat monitoring, then it is doubtful that it will conduct the assessment. One commenter was concerned that a system might opt to conduct the assessment instead of taking the repeat samples and just indicate in the assessment form that no sanitary defect was found or the cause of the total coliform-positive sample could not be identified. The system then avoids the possibility of the repeat samples being total coliform- or

E. coli-

positive. They commented that since the Level 1 assessment is done by the system, doing the assessment will also be cheaper than taking the repeat samples.

EPA disagrees that the PWS will avoid taking repeat samples because of economic reasons. EPA's analysis indicates that a Level 1 assessment costs about four times as much as taking three repeat samples (see Exhibits 3-12 and

4-7 of the

Technology and Cost Document for the Final Revised Total Coliform Rule

(USEPA 2012b)). States also must review the assessment form submitted by the PWS. If the assessment and/or corrective action is/are not acceptable to the State, the State can require the PWS to redo the assessment and submit a revised assessment form. EPA also expects that in situations where the cause of the total coliform- or

E. coli-

positive result cannot be identified, the PWS will arrive at this conclusion only after due diligence on its part (i.e., the system adheres to proper procedures and standards set by the State in conducting the assessment). The State may require the PWS to provide supporting documentation and analyses to back-up its finding. Because of the cost and the effort involved in conducting a Level 1 assessment, EPA expects that systems will want to ensure that assessments are conducted only when potential problems may exist rather than for failure to take repeat samples.

One commenter suggested that EPA clarify that collecting samples outside the 24-hour required time is not a Level 1 trigger as there are instances when the repeat samples cannot be collected within 24 hours of the routine total coliform-positive sample. EPA notes that there is a provision in the RTCR, § 141.858(a)(1), that allows the State to extend the 24-hour limit on a case-by-case basis if the system has a logistical problem in collecting the repeat samples within 24 hours that is beyond its control. In such cases when the State allows the system to collect the repeat samples beyond the 24 hours, the system does not trigger a Level 1 assessment.

One commenter suggested that EPA include an additional provision that an assessment need not be triggered if the total coliform-positive occurred when there are representative levels of disinfectant residual in the distribution system, stating that historical total coliform-positive results occurred with normal levels of chlorine residuals in the distribution system and did not cause any waterborne disease. EPA disagrees that there is no public health risk in this situation. The fact that total coliforms can be detected even in the presence of a disinfectant residual is an indication that there might be a bigger, hidden problem that needs further investigation. An assessment is warranted to determine if there exists a potential pathway of contamination into the distribution system and corrective action is warranted if a sanitary defect is identified.

EPA received comments to eliminate the Level 2 treatment technique trigger where a second Level 1 assessment is triggered within a rolling 12-month period, or for systems on annual monitoring, where two Level 1 assessments in two consecutive years trigger a Level 2 assessment. Some of the commenters thought that many small systems will be triggered to conduct a Level 2 assessment multiple times. EPA believes that although the conditions (i.e., a second Level 1 trigger) that lead to the Level 2 trigger do not necessarily pose an immediate acute public health threat, it may still pose a potential serious health impact because of the persistence of the contamination and the failure of the system to address it. EPA believes that a Level 2 assessment is warranted in this case because a more in-depth examination of the system is needed to determine the cause of the persistent occurrences of total coliforms. EPA also notes that, ideally, a well-performed Level 1 assessment and appropriate corrective action will prevent most systems from developing conditions that lead to a Level 2 assessment.

2. Assessment

a. Requirements.

There are two levels of assessment based on the associated treatment technique trigger: Level 1 assessment for a Level 1 treatment technique trigger and Level 2 assessment for a Level 2 treatment technique trigger. At a minimum, both Level 1 and 2 assessments must include review and identification of the following elements:

• Atypical events that may affect distributed water quality or indicate that distributed water quality was impaired;

• Changes in distribution system maintenance and operation that may affect distributed water quality, including water storage;

• Source and treatment considerations that bear on distributed water quality, where appropriate;

• Existing water quality monitoring data; and

• Inadequacies in sample sites, sampling protocol, and sample processing.

The system must conduct the assessment consistent with any State directives that tailor specific assessment elements with respect to the size and type of the system and the size, type, and characteristics of the distribution system. The PWS must complete the assessment as soon as practical after the PWS learns it has exceeded a treatment technique trigger. Failure to conduct a triggered assessment is a treatment technique violation. See section III.F.1.b of this preamble,

Coliform treatment technique violation.

Level 1 Assessment

A Level 1 assessment must be conducted when a PWS exceeds one or more of the Level 1 treatment technique triggers specified previously. Under the rule, this self-assessment consists of a basic examination of the source water, treatment, distribution system and relevant operational practices. The PWS should look at conditions that could have occurred prior to and caused the total coliform-positive sample. Example conditions include treatment process interruptions, loss of pressure, maintenance and operation activities, recent operational changes, etc. In addition, the PWS should check the conditions of the following elements: sample sites, distribution system, storage tanks, source water, etc.

Level 2 Assessment

A Level 2 assessment must be conducted when a PWS exceeds one or more of the Level 2 treatment technique triggers specified previously. It is a more comprehensive examination of the system and its monitoring and operational practices than the Level 1 assessment. The level of effort and resources committed to undertaking a Level 2 assessment is commensurate with the more comprehensive investigation and review of available information, and engages additional parties and expertise relative to the Level 1 assessment. Level 2 assessments must be conducted by a party approved by the State: the State itself, a third party, or the PWS where the system has staff or management with the required certification or qualifications specified by the State. If the PWS or a third party conducts the Level 2 assessment, the PWS or third party must follow the State requirements for conducting the Level 2 assessment. The PWS must also comply with any expedited actions or additional actions required by the State in the case of an

E. coli

MCL violation.

Assessment Forms

The PWS must submit the completed assessment form for either a Level 1 or Level 2 assessment to the State for review within 30 days after the PWS learns that it has exceeded the trigger. Failure to submit the completed assessment form after the PWS properly conducts the assessment is a reporting violation (see section III.F.1.d of this preamble,

Reporting violation

). If the State determines that the assessment is insufficient, the State will consult with the PWS. If the State requires revisions after consultation, the PWS must submit

a revised assessment to the State on an agreed-upon schedule not to exceed 30 days from the date of the initial consultation.

The completed assessment form must include assessments conducted, all sanitary defects found (or a statement that no sanitary defects were identified), corrective actions completed, and a proposed timetable for any corrective actions not already completed. Upon completion and submission of the assessment form by the PWS to the State, the State must determine if the system has identified the likely cause(s) for the Level 1 or Level 2 treatment technique trigger and, if so, establish that the system has corrected the problem(s). Whether or not the system has identified any sanitary defects or a likely cause for the trigger, the State may determine whether or not the assessment is sufficient, and if it is not, the State must discuss its concerns with the system. The State may require revisions to the assessment after the consultation.

b. Key issues raised.

The RTCR requires assessments to identify whether potential pathways of contamination into the distribution system exist after monitoring results indicate the system has exceeded a trigger. However, some commenters disagreed that requiring assessments will result in better public health protection. For one, they stated that assessments are already occurring under the 1989 TCR; hence, there is no need to formally require them. Second, assessments conducted by small systems will not likely be adequate as these systems usually do not have the resources and the capability to conduct a proper assessment. The States will then have to perform the assessments themselves (even the Level 1 assessments), thus adding to State burden. Third, assessments will reduce follow-up sampling and will allow a PWS to “guess assess” the cause of the positive sample.

EPA agrees that there already is some level of assessment and corrective action being performed voluntarily by proactive systems, and accounted for this fact in the economic analyses for the final RTCR (see chapter 7.4.5 of the RTCR EA (USEPA 2012a),

Assessments

). However, not all systems are proactive in addressing the probable cause(s) of the positive samples. Under the 1989 TCR, when a system has an MCL violation and any subsequent sampling did not detect total coliforms, the problem may persist despite the subsequent negative samples due to the intermittent nature of microbial contamination and may remain unaddressed. By requiring PWSs to assess their systems when they are triggered to do so, the RTCR aims to build and strengthen the capability of PWSs in ensuring that their systems maintain their integrity and that barriers are in place and are effective. These actions will better protect public health than the additional monitoring with no assessment and corrective action that is allowed under the 1989 TCR.

EPA acknowledges that small systems, especially small NCWSs may not have the knowledge and the resources that other systems, like CWSs, have. However, most small NCWSs are simple systems that often consist of just the source water and a limited distribution system. EPA anticipates then that the level of effort and expertise needed to conduct a Level 1 assessment at these systems will not be considerable. At a minimum, the Level 1 assessment should be conducted or managed by a responsible party of the PWS. While EPA does not expect the Level 1 assessor to be an expert in the requirements of SDWA, the assessor should be someone familiar enough with the system to answer the questions in the Level 1 assessment form or to gather correct information from others who work for the system.

To help in the implementation of the assessment, a PWS may conduct a Level 1 assessment while it consults with the State by phone. This is in lieu of having the State physically perform the assessment when the PWS needs assistance. Generally, the PWS would still need to fill-out the assessment form and submit it to the State. The State would still need to review the form but the process will not take as much effort as previously anticipated since the State would already be familiar with that particular assessment. It is also permissible that the State fill out the form while the PWS consults with the State by phone when doing the assessment. The State may also want to set up alternative methods for the PWS to submit the assessment form, such as via an online submission or email. The State should document its process in the primacy application.

EPA disagrees that the assessment requirements will reduce follow-up sampling. PWSs are still required to take repeat samples following a routine total coliform-positive sample. PWSs on quarterly or annual monitoring must conduct additional routine monitoring the month following the total coliform-positive sample. In addition, nothing in the treatment technique requirements precludes a PWS from taking additional compliance samples or special purpose samples such as those taken to determine whether disinfection practices are sufficient following pipe replacement or repairs (see § 141.853(b) of the RTCR).

EPA disagrees that PWSs conducting the assessment will “guess assess” the cause of the positive samples. Conducting an assessment is a methodical process that requires a PWS to evaluate the different elements of its operation and distribution system (§ 141.859(b)(2) of the RTCR specifies the minimum elements that an assessment must have, keeping in mind that some of the elements may not be applicable to some PWSs like small NCWSs). The RTCR requires that an assessment form be completed. The assessment form should help and guide the PWS in conducting the assessment by laying out the different elements the PWS must look into. EPA provides examples of assessment forms that States and PWSs can use to help them in conducting the assessment (these examples are given in Appendix X of the AIP (USEPA 2008c) and in Appendix A of the

Proposed Revised Total Coliform Rule Assessments and Corrective Actions Guidance Manual—Draft

(USEPA 2010d)). EPA also acknowledges that an assessment will not always identify sanitary defects or find a reason or cause for the presence of total coliforms and/or

E. coli.

In such cases, the PWS must document that fact in the completed assessment form. This, however, is not “guess assessing” as EPA expects that only PWSs that adhere to proper procedures and standards set by the State are eligible to arrive at this determination. It is then the responsibility of the State to determine if the assessment was acceptable.

Some commenters suggested that for systems with limited distribution systems that have a first Level 1 trigger, the Level 1 assessment should be delayed and the focus of the evaluation should be on the source water, and the Level 1 assessment should only be conducted if there is another Level 1 trigger.

The system may conduct an integrated assessment that meets the requirements of all applicable rules, such as the GWR and the RTCR, as long as the assessment is consistent with any State directives that tailor specific assessment elements with respect to the size and type of the system and the size, type, and characteristics of the distribution system, as required under § 141.859(b)(2) of the RTCR. EPA further notes that source water issues are one of the elements that need to be considered in a Level 1 (or 2) assessment where they may be a contributing factor to a coliform exceedance or other trigger. EPA expects that assessments at PWSs

with limited or no distribution systems will be relatively simple assessments and can be tailored to meet applicable requirements of both the GWR and the RTCR. EPA will address this in the revised

Revised Total Coliform Rule Assessment and Corrective Actions Guidance Manual

that is being developed.

EPA received comments both in support and against having two levels of assessment. The commenters in the second category concluded that both levels of assessment would involve the same effort. There were comments to eliminate the Level 1 assessment and emphasize the Level 2 assessment, as the Level 1 assessment will not lead to any meaningful evaluation and will only take up the State's resources. EPA disagrees that there is no need for two levels of assessment. The RTCR requires two levels of assessment to recognize that a higher level of effort to diagnose a problem should be applied to situations of greater potential public health concern such as repeated Level 1 triggers or an

E. coli

MCL violation. A Level 1 assessment is not as comprehensive as Level 2 assessment. This however, does not negate the importance of a Level 1 assessment. Triggers that lead to a Level 1 assessment may indicate the possibility of a breach of the barriers in place. It is important that PWSs ensure that these barriers remain intact by performing the assessment.

EPA received comments that the qualifications of assessors are not clear in the rule. The commenters suggested including the qualifications in the rule or referencing the qualifications described in the

Proposed RTCR Assessment and Corrective Actions Guidance Manual—Draft

(USEPA 2010d). Some commenters concluded that the Level 2 assessment will require a whole new certification program for assessors. Others concluded that the States will end up doing the Level 2 assessment because of what is expected and required of a Level 2 assessment. On the other hand, one commenter suggested that a system operator should be certified to perform an assessment of their own system. Another suggested that States be allowed to set mechanisms in place to ensure that a Level 2 assessment is performed more comprehensively than a Level 1 assessment.

EPA does not require that a separate certification program be established to determine who can perform a Level 2 assessment. Instead of being prescriptive on who can conduct a Level 2 assessment, EPA is allowing the State to determine its criteria and process for approval of Level 2 assessors and to determine who is appropriate to conduct the assessment given the State's knowledge of the complexity of the system and the knowledge and policies of the State. Although the rule allows that certified operators may perform a Level 2 assessment if approved by the State, EPA recommends that States consider whether having the assessment done by someone from outside the system can provide a fresh perspective. Qualified certified operators can be allowed to conduct assessments at other systems.

EPA requested comments on how to ensure that a Level 2 assessment is more comprehensive than a Level 1 assessment (e.g., by possibly including asset management and capacity development). EPA asked in the proposed rule whether EPA should provide more detail in guidance or rule language, on the elements and differences between a Level 1 and Level 2 assessment. A majority of the commenters were against the inclusion of asset management and capacity development in the Level 2 assessment. EPA received comments stating that the proposed rule language regarding the two levels of assessment was adequate and that additional discussion about the differences between the two should instead be addressed in guidance. One commenter, on the other hand, said that there was no difference in the scope between the two assessments based on the way the proposed rule language was written.

EPA defined in § 141.2 both a Level 1 assessment and a Level 2 assessment to provide a better distinction between the two levels of assessment and facilitate the implementation of the RTCR. See section III.A.1 of this preamble,

Assessment,

for the definitions of a Level 1 and Level 2 assessment. EPA is also requiring States to describe in their primacy application how they will ensure that a Level 2 assessment is more comprehensive than a Level 1 assessment; thus, giving the States more flexibility in implementing the rule. EPA released the

Proposed Revised Total Coliform Rule Assessments and Corrective Actions Guidance Manual—Draft

(USEPA 2010d) in August 2010 to help stakeholders understand the difference between the two levels of assessment. EPA will revise this guidance manual based on the comments received and release it soon after the final RTCR is published in the

Federal Register

.

EPA received comments to allow the extension of the assessment period beyond 30 days. A commenter suggested that intermediate deadlines for a Level 2 assessment triggered by the presence of

E. coli

be included because of the acute nature of the threat.

EPA expects that the PWS will conduct an assessment as soon as practical after the PWS receives notice or becomes aware that the system has exceeded a trigger. EPA imposes a 30-day limit because the possible occurrence of contamination, as indicated by the conditions that trigger the assessment, must be addressed immediately. The system has 30 days from the time it learns of exceeding the trigger to conduct the assessment and complete the corrective action. EPA believes that the 30-day period is sufficient time for problem identification and potential remediation of the problem in conjunction with the follow-up assessment in most cases. The s

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